There are a number of different makes on the market, and I'm not sure there's really any difference. In particular, Sarah highly recommends the strapless version of the ultra bra, but it might be worth experimenting to see which suits you best. But you can certainly get a 38A in the Wonder bra and Ultra bra. Note also that you may be able to get away with a size below that which you ought to be wearing, and if you're, say, 37in, it is definitely worth trying 36in. Note too that though black bras are fun, they are all but useless under anything other than a black top or dress.
First priority is to dispose of the masculine contours.
First push the testes back up whence they came. For a description, cf. It's easier for the younger of us, but it should be manageable for all. Be gentle, and don't force them. Then deposit penis between legs.