False nails are fine, I use them and nail varnish all the time. However, the smell makes me feel a bit funny so I've not used them as often as I normally do during pregnancy. Make sure if this happens you can leave the room and go outside to breathe for a bit.

Bleach makes me feel really ill, so I just cannot use that, but use all other products with no problem. Again, make sure you're well ventilated or teach your man how to do it! (Yeah, that didn't work for me either.)

Skin - I found mine was quite bed in the first trimester, but was fine for the second and third; it's only now I'm overdue that it's started to get bad again. But you can always use tee-tree oil or witch hazel gels on your spots to clear them up.

Good luck and enjoy being a bridesmaid!