Wow. My first inkling of being transgender was when my dad took me to the beach when I was about five years old. For the first time in my young life I saw women in bikinis. (I had never even been to a public pool before that -- I led a really deprived childhood). When I saw those women at the beach, my first thought was, "That's what I want to be!" For years afterward I rolled my underwear down into bikini bottoms/panties every chance I got.
From the time I was 19 until last year, I always wore speedos and men's bikinis -- that was my coping behavior while I was in denial about being transgender.
I am pre HRT and now wearing women's bikinis at home in my pool. I have a pretty high level of privacy -- I only need to fool the police helicopters that occasionally circle overhead and possibly a neighbor's gardener who catches a quick passing glimpse through a crack between the fence boards. But I still want to look as female as possible.
So here goes:
1) Decide whether you are swimming or not. Most women have two different looks, one for staying dry at poolside, and a whole different one for actually going in the water. If you are staying dry, things get a lot easier, because you can do full makeup, jewelry, and throw a wrap skirt or pareo around the bikini bottom to hide a lack of curvature in that area. You can also wear padding under the bikini without worrying about what happens when the foam soaks up a gallon of water, or the water dissolves the adhesive on your double sided tape. A sun hat and big sunglasses can save you a lot of work on the makeup. Women generally do not wear makeup or jewelry to actually go swimming, so passing becomes a lot harder if you are going in the water in public. If you have to use a wig and contouring makeup, then go wading, and keep your head out of the water. Or just go hot tubbing instead.
2) If you have a gut, either diet or exercise it off, or resign yourself to wearing a one piece suit with some tummy control built in. If you are going to exercise, then go heavy on lunges and squats, to develop your hiney. That is the part women like to draw attention to these days, and doing so saves you from having to worry too much about breast forms.
3) Shave everything, and I mean everything.
4) Women might not wear makeup into the pool, but they do wear nail polish. Color coordinate your nail polish with your bikini.
5) Instead of breast forms, try to find bikini tops with padding built in. They exist, and are pretty easy to find. They are intended to help women keep their nipples from showing through the fabric (Go watch Geena Davis in "Earth Girls are Easy" and you will see what I mean about show through) but even those thin pads will help it look like you have something up top.
6) Use triangular breast forms if you must use forms. There are forms out there that are designed to fit under bikini tops. Note that I do not recommend wearing forms while swimming. There is too much that can go wrong when you move around that much.
7) Unless you are pretty narrow in the shoulders, stay away from bandeau tops. Wear a halter top instead. If you must wear forms, try to get a halter top that covers the breasts all the way to the top, and the area between the breasts, so as to conceal the edges of the forms.
Bottoms: I do not recommend wearing padding under bikini bottoms unless you won't be going in the water. I have yet to see the padding that can effectively simulate the look of body fat under wet spandex. I do recommend trying to find bikini bottoms that are as wide in the crotch as possible. You are going to have to do some form of tuck, but just how much of a tuck depends on how closely you are going to be seen.
I'm a little on the small side, so with a Victoria's Secret itsy, I just tuck the boys up into the inguinal cavity and pull the shaft back between them. It leaves a nice little bulge that doesn't look like a female cameltoe, but is not obviously male, either.
If you are dead set on passing in a bikini from close range, then Koala Swimwear has some men's thong swimsuits that can force a tuck that looks just like a vagina. They call them "feminizing" suits but a lot of transgirls wear them as gaffes. They are a little pricey, and no comment on whether you will still be fertile afterward, but if you wear one of those under a more conservatively cut women's bikini bottom, it should work pretty well. Otherwise, use a really tight gaffe.
Stay away from skimpy string side bottoms unless you are slender or have a really feminine looking lower body. Go with bottoms that have one inch or wider sides. Also stay away from high waist bottoms unless you are slender.
You may want to consider sports bras, short women's board shorts, or bikinis made of wetsuit material.
So those are all my random notes on wearing bikinis. I just put in a big order at Victoria's Secret, and I am planning on many happy days at my pool this summer.
