Tutorial: How to make an adjustable shoulder strap

It's all about the zippers bagMy all-time favourite strap to have on a bag is an adjustable shoulder strap. They give your handmade bags a very professional look and while they may seem daunting to make at first glance, once you know what to do they’re actually very easy to make.


Handmade bag to attach the strap to.

Fabric to make the strap or a store bought strap. I have no idea what the correct English term is for that product but in Dutch it is called “tassenband”.

supplies adjustable shoulder strap1 slider. I recommend using a 1.5’’ (3.75 cm) or 2’’ (5 cm) wide slider because anything smaller means that the straps will be a real pain to turn right side out. Sliders come in different colours and materials. I prefer to use metal ones but you can also get plastic ones, like the one in the picture. Sometimes the centre bar of the slider can move a little bit.

2 D-rings, the same size as the slider. These can be D-shaped, rectangular or even O-rings. You can also get D-rings that have a musketon attached to them so you can make a removable shoulder strap. If you decide to use those you will still need to attach regular D-rings to the bag so you have something to attach the musketons to.

For my “it’s all about the zippers” bag I used a 1.5’’ slider and D-rings. The outside of the strap was made with the fashion fabric and the inside (the side that touches the body) was made with the lining fabric. Both fabrics were interfaced, the fashion fabric with a very lightweight woven fusible and the lining fabric with a medium weight woven fusible. I usually interface my straps but if you use a sturdy fabric for both sides, such as denim, it is not always necessary.


An important part of making your strap look professional is to get the width of the strap spot on. If it is too narrow the slider will be able to move sideways on the strap and the slider will move too easily up and down the strap resulting in a less secure strap. It will also look wrong. If it is too wide, the strap will bunch up in the slider and it will be difficult to move it up and down the strap. On a good strap the slider has a little bit of sideways movement (really just a tiny little bit), it doesn’t bunch up inside the slider and the slider moves up and down the strap relatively easy. To make sure that your strap will be spot on I highly recommend that you first make some small samples to test what fabric width and seam allowance will give you the best result. My slider was 1.5’’ wide and I cut my fabric straps 2 1/8’’ (5.3 cm) wide and sewed with a ¼’’ (6 mm) seam allowance to get the perfect fit. It might be different for your fabric so test this! You may have to play a bit with the seam allowance, for example by moving the position of the needle a bit to the left or to the right. Investing the time to do this will most likely prevent major disappointment later on, so don’t say I didn’t warn you! If you intend to interface your strap you should also do this with your sample.


Step 1: Sewing the fabric strap is usually the last thing I do when I make a bag. Make sure that you have attached your D-rings to the bag at some point during the construction stage. On the bag I used for this tutorial I attached the D-rings with a fabric tab to the front and back of the bag. The fabric tab was made by sewing a rectangle of the black canvas and black Kona cotton right sides together, leaving a gap on one of the long sides to turn right side out. The tab was then sewn to the front and back pieces with 2 crosses (see step 12 on how to sew a cross) with the straight part of the D-ring in between.  Another method is to make a fabric loop and insert this with the D-ring in between the fashion fabric and lining when these are sewn together at the top of the bag. The fabric loop is constructed the same way as the strap but the short ends can be left open.

adjustable shoulder strap

Left: D-ring attached with fabric tab. Right: D-ring attached with fabric loop.

Step 2: Decide how long your strap should be. What I usually do is hold the bag where I want it to rest as I carry it, pretend my tape measure is the strap and measure the distance from one D-ring to the other. Then add at least 8’’ (20 cm) to that measurement but feel free to be more generous. For narrow bags the strap usually has to be a bit longer than for wider bags. For my bag I cut my fabric strips a little over 56’’ (140 cm) long; this was basically the width of the piece of red fabric. If your fabric isn’t wide enough to cut a strip that is long enough for your strap it is perfectly all right to piece the strap. I do recommend that you do this the same way two pieces of bias tape are sewn together (with a 45 degree angle) to avoid bulk in the strap. I’ve shown how to do this in this tutorial.

Step 3: Cut your fabric strips on the straight of grain and interface if desired. I cut my interfacing ¼’’ (6 mm) narrower than my fabric to reduce bulk in the finished strap.

adjustable shoulder strap

Step 3

Step 4: Pin the two pieces of fabric right sides together and sew around all edges. Leave a gap at the centre of one of the long edges for turning right side out and backstitch at the beginning and end.

adjustable shoulderstrap

Step 4

Step 5: Trim the corners but don’t get too close to the stitching.

adjustable shoulder strap

Step 5

Step 6: Press the seam open. I suppose this step isn’t strictly speaking necessary but I find that I get a much neater finish on the strap if I take the time to do this. I place the strap on my ironing board and fold the seam allowance of the top fabric over to press. I do this to both sides.

adjustable shoulder strap

Step 6

Step 7: Turn the strap right side out through the gap. This can be a bit of a struggle, I usually go and watch some television while I do this. The corners can be a bit tricky to get nice and square (I never manage exactly square to be honest) and you can use a chopstick or something similar to give them a gentle poke.

Step 8: Roll the seam between your fingers to help it lie flat. Press the strap flat using your iron. I always press with the outside fabric up first. Press the edges of the gap you left for turning to the inside so that you can no longer see where the gap is located.

adjustable shoulder strap

Step 8

Step 9: Topstitch around all edges. It is important to make sure that your topstitching is close enough to the fabric edge to catch the seam allowance. This guarantees that the gap that you left for turning ends up closed. If you are using 2 differently coloured fabrics, change the bobbin thread so that it matches the inside fabric.

Step 10: Now we’re onto the fun part: weaving the strap around the D-rings and slider. I always do a test run before I start sewing to make sure that everything will end up as planned. To do this pin the ends in place instead of sewing while folding the strap.

Step 11: A slider usually has a front and a back. Place it on the table with the front side facing down. Thread one end of the fabric strap around the centre bar of the slider with the outside fabric facing down as well.

adjustable shoulder strap

Step 11

Step 12: Fold the end of the fabric strip back over itself so that the inside fabric touches the inside fabric. Pin in place, and sew a cross to secure the end. If you changed your bobbin thread for the topstitching in step 9 you should change it back to match the outside fabric. The slider is now encased in the strap. The slider doesn’t need a lot of room but it should be able to move somewhat.

adjustable shoulder strap

Step 12

Step 13: Decide on which side you want the slider to end up. I wanted mine on the back of the bag. Take the strap end that is not attached to the slider and thread it through the D-ring on the side you want the slider to end up. The outside fabric should face the bag and you should insert the strap from the top. Fold the strap back up over the D-ring and thread it through the slider.

Adjustable shoulder strap

Step 13

Step 14: Now the free end of the strap should be wrapped around the other D-ring. Insert the strap through the D-ring from the bottom, fold it back down over the D-ring, pin in place, check you didn’t accidently twist the strap and sew a cross to secure.

Adjustable shoulder strap

Step 14

Step 15: Adjust the strap to your preferred length and you are done!

Have I convinced you to give this type of strap a try on your next bag? I’d love to see your bag if you give this method a try!

Pattern testing: Presidio Purse

First of all I would like to wish all my readers a very happy new year! I hope 2014 will bring you more than you expect. This year promises to be a busy one for me as I intend to finish this thing called a PhD thesis so that I can defend it in 2015. I also want to spend plenty of time crafting though as I find that this helps to keep me sane and happy.

I was lucky enough to be one of the pattern testers for SeamstressErin’s first pattern, the Presidio Purse. This was my first time testing a pattern and I thoroughly enjoyed it. Usually I make my own pattern when I want to make a bag and then I mostly use rectangles, so it was fun to make a bag that has some curves to it.

Presidio_purseErin describes this bag as an oversized hobo style handbag and it certainly is huge. It is the largest bag I have ever made and you can stuff almost infinite amounts into it, like Hermione Granger’s bag in the last of the Harry Potter books. In December I spend two nights out of town to visit a conference and this bag was all I took and it was nowhere near full. The bag is carried over the shoulder and has a top opening zipper. The front has two options for insets and there are also two options for the shoulder strap, with and without D-rings. On the inside there are two pockets, one with a zipper and one patch pocket that is divided into 3 separate pockets.

Presidio_PurseThe pattern comes as a PDF, so you have to do some assembling before you can start sewing but I think it took me less than 30 minutes to piece the sheets together and cut the pattern pieces out of the paper. Alternatively, you can take the printshop version to a printshop and have them print it for you on one large piece of paper and avoid assembling. The 1/2” seam allowance is already included in the pattern. I’m not really a fan of a 1/2” seam allowance because it doesn’t translate as well to a metric measurement as 3/8” or 5/8” but I had no problems assembling this bag and I can’t remember unpicking anything during the construction. The instructions in the test version were already clear enough for me to make this bag without issues but in the final version they’ve become even better, Erin clearly took all our advice to heart. I really like the drawings that illustrate the more challenging construction steps.

zipper and liningBecause there is a bit of time pressure when you’re testing a pattern I decided to just get started as soon as possible and use materials from my stash instead of going fabric shopping. For the outside I used left-over fabric from my living room curtains that I interfaced with medium weight fusible woven interfacing (according to the sewing instructions I didn’t need to interface but I did it anyway because I don’t like floppy bags, call me a rebel). For the lining I used an Indonesian batik that was a gift from my mother. I am glad I was finally able to use it in a project and I think it works very well with the curtain fabric and the pink zippers. I also used it for the bottom of the handle and the zipper tab because I wanted to add some additional interest to the exterior.

If you want to dip your toes into bag making this bag might be just the ticket because Erin is going to host a sew along on her blog so you’ll be able to follow each construction step and ask questions along the way. She will also show some extra options that are not included in the pattern such as how to add piping and extra pockets.

I plan to make another version for myself with an adjustable shoulder strap and more pockets. I prefer to carry my bags across my body because that way they stay put when I cycle at top speed. I know some people are going to laugh about this because I’m not very fast, but hey, I meant my top speed, so stop laughing! I’d also like to play a bit with the insets because I think those offer a great opportunity for customisation.

Erin released the pattern for this bag today so if you want to know even more, please hop over to Erin’s blog!

Some detail shots.