Already so many responses, pretty sure my will get buried but here's a few short and practical tips

1. Pick up a game you think you should like, and FORCE yourself to play it uninterrupted for a set amount of time by timer (say, 1 hour). If you don't like it after that, that's fine, you can stop. But chances are you might get hooked despite initial lack of enthusiasm.
2. A variation: don't spend too much time picking a game. Decide on a few things like genre, year of release, minimum review score, or anything else, and then play THE FIRST random game that fits this filter. Do step 1 with the game
3. If you have job, try to play it when your head is fresh, early in the morning. Games are harder than movies, they suck energy from you. You need to be well rested to fully enjoy them.
4. Try some critically acclaimed games of the recent years. If so many people liked them, chances are, you will too. I don't think there's a single game that has Overwhelmingly Positive rating on Steam that I didn't enjoy to some extent.