My experience is that you're much more likely to succeed if you find people that want to play and make friends with them than you are making your friends play.

If you pitch to your existing friends, they're more likely to say yes because they're your friends. They want to hang out. But they might just be saying that to be nice or because they're afraid of confrontation. They might not realize you're looking for a commitment on par with joining a sports team. If they don't already play RPGs, they might not know they're going to have to do some reading and writing. A lot of people just don't read and creatively write. That can be difficult and embarrassing.

On the other hand, if you post online or in a local game store, you can find people who are ready to go. People who can already do your schedule and also know the game you want to play. There's a small risk of getting a weirdo, but a quick screening catches a lot of that.