Any tips?

Okay this is our 12th month trying and I'm just fed up and sad. I should be ovulating in about 3 days, I started using ovulation tests. I take prenatal vitamins, use conceive plus. Should we not have sex at all until the ovulation test is positive? Or have sex any time and still have sex when the ovulation test is positive? I'm open for any tips or anything. I'm becoming depressed, I want to be a mom more than anything in the world.