Has anyone ever used certain methods for gender determination?!

My husband and I are TTC. I have 4 boys, and have decided to try ONE MORE TIME for a baby girl. I have read, researched and studied several methods that are supposed to increase your chances of having the gender your hoping for. I want so badly to have a baby girl! I was wondering if anyone has tried these methods, and what the outcome was. Also, most everything I have read says female sperm live longer but are slower, and male sperm are faster but don't live as long. So if your want to conceive a girl have sex before ovulation and if you want a boy have sex on the day of and after. When in your cycle did you conceive and what gender was your baby?!