The number of different ways to promote a band are only limited to your imagination.
I have heard and seen many successful ways of doing it.
Getting your name out there is key but don't be fooled.
With so many people out there promoting themselves you can't just blast your name all over the place and expect a good response.
It's important to communicate with fans so they feel like they are talking with a real person rather than some bot that sends hype promotion every so often.
Get involved with social networking sites.
It's important to befriend people who share the same interest in music that you do.
Communicate with them, ask and answer questions.
Build a bit of a relationship with them and then drop the link to your website.
You should have an emailing list set up at your website.
Offer a free download of your demo or at least a song for everyone that signs up to your list.
This way you are giving the music away but in return you have there contact information so you can send them future updates and material.
Stay involved with the subscribers on your list by emailing them once a week or so.
Play a lot of live shows.
I know that this one is obvious but there is more to it then just getting on stage and playing your music.
First work real hard on perfecting you live show.
On stage your set should look effortless and energetic.
Know your songs so well that you can play them in your sleep.
Be professional, and have a table or booth set up some were at the venue that has your merchandise and music.
Also have a mailing list at your booth.
This list should be real simple and is just for contact information.
The list should ask for there name and email address, that's it.
Try using this simply tips for your band.
Just making this little changes will help your promotion efforts and grow your fan base.