Tinder users tend to swipe fast, so you may have only a couple of seconds to grab someone's attention. The first thing she's going to see is your main photo, so it's got to be amazing. Yes, all of your photos need to be good, but the first one is doing the most work.
How do you pick the right shot? Get some help!
Ask your friends to help, and ask some women their opinions if you can. It's hard to be objective about our own image, so outside input is very important here.
You can also get some professional help picking the best photos for online dating.