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.