I think this is my favourite version of Cottesloe – the low back one piece! Today we will go over all the steps in the View A construction leading up to elastic insertion – shelf bra, foam cups, ties, and then suit seams. The shelf bra/cups and ties are optional, but definitely add better support for the low back design.
This is such a great option if you like the classic shape of Cottesloe, but want a little more detail compared to the basic one piece that is View B. Gah, I just love this version! So let’s get started!
SHELF BRA + OPTIONAL FOAM CUPS

Cut your shelf bra 1/2″ elastic per the measurements provided in the cut instructions for View A.
Pin each end of the 1/2″ elastic to the bottom side seam edge of the shelf bra, on the wrong side of the fabric.
Sew the elastic to the shelf bra using a zig-zag stitch. Stretch the elastic as you go to match it up with the length of the fabric.
You will be lining up right along the bottom edge of the shelf bra, and sewing right through the centre of the elastic.
Turn the elastic and fabric edge in towards the wrong side of the fabric.
With a zig-zag stitch again, sew right along the raw edge of the fabric/elastic to enclose.
From the wrong side, you will see two rows of zig-zag stitches, but from the right side, you will only see one.
If you are adding foam cups – flip your shelf bra over so the right side of the fabric is facing you. Place the foam cups right side down in your desired position and pin in place.
Note: There are many different shapes and sizes of foam cups. Find the best one for your body. And there is also no “one size fits all” position for the cups. Hold the shelf bra up to your body to find your ideal cup position.
Zig-zag stitch around the very edge of the cups to attach to the shelf bra.
Flip the shelf bra over to the wrong side, and trim away the shelf bra fabric from over the cup.
Now place your Front suit piece down in front of you with the wrong side of the fabric facing you.
Place the Shelf Bra on the Front with wrong sides together. Pin together at the shoulder seams and seams.
The Front/Shelf Bra will now be treated as one piece of fabric when sewing.
Optional: you can sew the shelf bra to the front at the side seams and shoulder seams instead of just pinning it if you would like to secure it more for sewing. Use a zig-zag stitch and stitch close to the edge.
TIES
Fold the ties in half widthways with right sides together and pin.
Sew each tie 1/4″ from the raw edge along the long edge and the pointed short edge. Use a zig-zag stitch or serger/overlock.
Turn the ties right side out through the open short edge.
Place your Front down in front of you with the wrong side facing you.
Place the ties down on the wrong side of the fabric, so the open short ends line up with the side seams, and the seam of the ties lines up with the elastic of the shelf bra underbust. Pin in place (you can also zig-zag stitch together to secure better for the next step).
SUIT CONSTRUCTION
Now turn your Front piece over so the right side is facing you.
Place your Back piece down on top so right sides are together. Align the shoulder seams and side seams and pin in place.
At the crotch, place your Gusset piece right side down on the Back. Pin in place through all three layers of fabric (gusset, back, front).
Note: you can cut your Gusset out of self fabric or swimsuit lining.
Sew along the shoulder seams, side seams, and crotch seam 1/4″ from the raw edges using a zig zag stitch or serger/overlock.
At the crotch, you will be sewing through three layers of fabric.
If you added the shelf bra and ties, you will also be sewing through multiple layers of fabric at the shoulders and bust as well.
Once again, flip your suit over so the Front is facing you (still wrong side of the fabric), with the Gusset flipped down.
Flip the Gusset up towards the Front, so that the right side of the Gusset fabric is now facing outwards. Pin the Gusset to the front leg openings to keep it in place for elastic insertion. We will go over elastic in another post!
LOOKING FOR MORE COTTESLOE POSTS?
Here’s the full list of Cottesloe posts and tutorials:
- Pattern Tester Round-up
- Inspiration + Ideas
- Where to Find Swimsuit Fabric
- View B Full Suit Construction (+ Optional Lining)
- View A Full Suit Construction with Shelf Bra and Ties (this post!)
- Views C & D Bikini Construction
- Basic Elastic Insertion for All Views
- Waistband and Underband Elastic Insertion for Views C & D
We absolutely love seeing what you make, so don’t forget to tag your creations with #MNcottesloe and @megannielsenpatterns when sharing on social media, and check out what everyone else is up to!
Don’t have the Cottesloe pattern yet?
