Peeing on baking soda if it fizzes its a boy if it doesn't its a girl, the ring on the string test, and you can google some more. I did the baking soda one and it said girl and she was a girl, but its 50/50 so it could be wrong also. I got my scan done a 20wks to find out gender.
16 weeks a 3D/4D Scan can give you a answer, no old wives tales work so you'll need to get the scan or wait till you have the baby
good luck x
Heard that if your belly is more round shaped its a girl and if your belly sticks out farther its a boy..turned out true for me (: