Step 1: Materials
I ended up using almost a yard of lycra and half a yard of the power net (a stretchy mesh). This was mostly because I was experimenting a lot. Once you have your pattern made, you should easily be able to determine how much material you need.
I opted for two bottle openers, which I got from Amazon.com.
I also used swimsuit elastic for the bottoms (won't break down in chlorine), and clear elastic for the top, and a hook for the back.
You can also add modesty cups for the top, or underwires, or even padded cups. I tried this out, and decided not to use them.
Step 2: Pattern
Decide on what shape you want your beerkini to be. I'm sure this would also work as a one-piece with an inset bottle opener too!
I used a couple swimsuits I already had to draft some patterns, chose one, and tweaked it from there. I am fortunate to have a dressform that is approximately my size to pin things to and fuss with the shapes. My next version would definitely have a more modest bottom. I'm really not sure I would wear this in public.
I've attached the pattern I used for you to use, tweak, or modify as you see fit.
Step 3: Cut Pieces
Make sure you align the lycra to one long edge of a table before you cut it so it's not all twisted and warped. Place your pattern pieces on the fabric and use weights to hold them in place. Pinning the pieces may lead to runs in the fabric.
Trace along the outside of the pattern with chalk, and then again about 3/8" or 1/2" outside of the line for seam allowance.
Cut along the outside line you've marked.
Step 4: The Bottoms
Picture 2) I pinned the mesh to the wrong side of the outer fabric and scatter-pinned them together so I could flat line them (sew them together flatly) without the layers shifting and twisting.
Picture 3) I machine-basted the pieces together with right-sides together
Picture 4) I used a baby-lock machine to serge the seams together. Using a serger or overlock machine allows the seams to stretch without breaking the threads. If you don't have access to this, you can use a zigzag stitch on a standard sewing machine.
Picture 5) I basted swimsuit elastic to the outer edge of the finished seam lines of the suit along the legs and waist.
TIP: Stretch the elastic along the back of the leg opening, but lay flat along the front.
Stretch the elastic along the waist evenly.
Picture 6) I serged the edge of the elastic to the fabric, being sure to cut off the excess fabric, but not cutting into the elastic
Picture 7) Elastic is serged to the suit
Picture 8) I turned the elastic to the inside of the suit so the folded edge is now the outer edge of the suit. I used a zigzag stitch from the front side of the fabric to sew down the edge, stretching as necessary.
Picture 9) I pinned and hand-basted the bottle opener into the suit opening. I later serged the raw edges to the inner layer of mesh, but this was pretty tricky, and you can get away with hand-sewing the whole thing, or taking it to a sewing machine and using a zig sag stitch through all layers.
Step 5: The Top
Picture 2) The same procedure was applied to the backs of the bikini top.
Picture 3) The straps were sewn together as indicated on the pattern, and elastic was serged to the seamed edge.
Picture 4) The fronts are turned right-side out (encasing the elastic on the inside), and gathered along the center fronts and sides. The gathered front edges were then serged to scrap pieces of lycra that will later be used to sew in the bottle opener.
Pictures 5&6) The straps are placed along the side edge of the front cups, basted and serged together.
Picture 7) I sewed the bottle opener to the front cups (this picture is actually from the bottoms, but the same technique was used)
Step 6: An Easier Way
Unless you are a lycra ninja (which I'm sure some of you are!), save yourselves the multiple headaches that I encountered in dealing with this slippery, fussy material (and I do consider myself a very experienced sewer, as it was my job for about 10 years), and just buy yourself a d$%n swimsuit. Cut it apart and sew in some bottle openers. Seriously. It will take you 20 minutes instead of 20 hours. And you know it will fit.
So there you have it! 20 minute custom beerkini!