Pregnancy

Hi so I need help.. i want to get pregnant with my significant other.. we have been having unprotected sex for almost 3 months now... there are time I show the signs I might be pregnant but I take a test and I’m not.. how do I know when I’m ovulating? Haven’t had my period at all this month.. but then again it never comes at the same time.. idk what to do any ideas on how to help this happen for us?