TTC! Need some advice!!!

Riley
I'm new to this site so bare with me. My bf and I have been trying for 8 month now and i don't know what I'm doing wrong. I tried conceive easy, then I tried an app, now I'm trying this app. I've had some people telling me to try and have sex before my period and I've had people tell me after. My period came the 18th which it normally come on the 24th, i don't know if that makes a difference. I've tracked my ovulation before but I quit doing everything because I just kept getting frustrated with negative tests. Advice???