We did gender sway with our 3rd, who is a boy. While we would have been happy with a girl, we figured why not try to sway the odds a tad? Who knows if it works, but we DID have a boy, so for us it did!
We timed dtd for 12 hours AFTER getting a blaring positive opk. Male sperm die faster, but swim faster, so you want them to get to an egg that's already been released. You don't want boy sperm to have to sit around waiting.
We used pre-seed to make the vaginal environment less acidic, again because it kills off the weaker boy sperm.
We used musinex cough syrup an hour before dtd. It thins cervical mucous just like mucus in the chest/throat, which makes it easier for boy sperm to get through. Just make sure it says "expectorant" on the cough syrup.
We used positions for deep penetration and ejaculation close to the cervix. You can google those. I won't go into it.
I think that's it! In-gender is a great website for swaying info, too.
Good luck!