Honestly, I have looked back at other bands I've been in and here are some lessons that all lead to a self-sustaining promotion machine that I have seen work many times:
* Professionalism: great website, professional photos, professional video, well produced music, well manufactured CDs, maintain social networking sites, youtube, whatever, email lists. Have a good attitude and zero ego with fans or anyone in the business.
* Quality: buy great PA equipment. buy great lighting. If you play at a typical small venue with a crap PA, people will think, "man, these guys sound shitty." But if you have a great PA and great lights, and epic bass, people will think, "Holy shit, these guys are insane," even if you suck ass.
* Be positive: My theory is that everyone is more or less miserable. If you are nice to them, to club owners, bartenders, other bands, if anything they will remember you as "That guy didn't make my life/job more difficult that night, that guy is easy to work with." Help the other bands move their shit so they can get out of there. Ask the bartender/owner, "How'd you guys do tonight? Hey, we like this place and had a great time and we'd love to help get some people in the door. Let us know if you want to set something up." Whatever, something.
* Put on a goddamn show: Put every last drop of energy into your show. I think you should literally be exhausted after a show. Have a reputation for being great. I think there is a lot of room in chip and electronic music to make a more exciting show. It is all too tempting and easy to just sit behind a laptop and do nothing. I think that it is great to sit behind a laptop when you make the music, but if you are out on a stage, you goddamn better entertain these people. This generation is pretty OCD -people have very short attention spans, so you have to constantly be entertaining and constantly change the show.