The way that this topic is titled is the wrong way to go about it. "Reddit" does not help promote a channel. Rather, you can be a contributor to subreddits, providing material that you think people would enjoy, only *some* of which might *happen* to be your own material.
If you think you can approach reddit just to promote yourself, then you're going to have a bad time. You have to be an active participant, not just an advertiser