3 suggestions:
1. I'd put an "announcement" type of post right on top which is a direct link right to a dating/cams offer. Make it sounds good "click-bait "type so people click - this the first thing new subscribers see and maybe you'll get a few signups. That's the easiest and laziest way and will make you less money. it's a little spammy but it's just 1 link.
2. More work and eventually more money is to make a website and post links to it mixed with your usual posts, like 10 normal posts and 1 to your website. Monetize the site with banner and CPA. Popup/popunder ads are tempting but Reddit mofos hate this shit passionately so IMHO try to stay away from those
3. Do some light SEO to the subreddit and try to rank in on g00gle for some money making KWs. reddit is the prefect parasite -
check this thread by
@710fla