First time using Ovulation tests

Hi all! This month is my first month using ovulation tests, but I'm confused. I've been testing the past 3 days and got a faint red line (you can clearly see it but it is not darker or as dark as the testline). So I know I'm not ovulating yet. But should we already start having sex to get pregnant or should we wait until the line is darker? Ps: we normally have sex whenever we feel like it, but I also want to make sure we have sex on my fertile days. So I can use any advise on using ovulation test. Confused 🤣