I was playing funky house for awhile, with a couple of mates, being paid.
Basically we did a lot of knocking on doors - bars we knew that had the right set up in terms of kit and potential customers. When we landed a one off gig, we then did alot of flyering etc and general talking the night up - alot of (I hate this phrase) networking.
We lost money on the nights that we were wholly ours (i.e. exclusive hires, tickets, etc), but touted ourselves around more, did a one off with a bar and rammed the place (queue down the street) who then offered us the Saturday night residency.
We were collectively paid £150 a night and drinks were free. Not really a living, but it funded our vinyl for awhile, and gave us some added credibility when touting for other gigs.
When weren't doing the residency, we did house parties for free provided the organiser rented decks and a PA. There'd usually be plenty of booze and other stuff laid on, and there was plenty of attention from women, which was nice.
If you're a bedroom DJ playing dance music, here's one route, based on my experience. It only works if your style can work in a bar...
Get out and get talking about yourself. If helps alot if you live in a city. Burn some demo CDs, get round every bar that has potential. If that means being out several nights a week just doing that, then that's what it takes.
It's worth trying to understand what each venue is about - what time of the day or week would your style work? Ask who arranges their music - don't bother pitching at anyone else. Be nice, be professional, be sober. It should be the main purpose of your visit. Don't decide to have a word after you've been in there for a couple of hours with your mates.
It's well worth finding a DJing partner to do it with. You'll be more confident in doing the rounds, and if there's more than 1 of you, you can more easily play a longer slot.