Right, so you are a musician and want to learn how to make money off of music? There are many ways to make money off of music, it just takes some hard work and some know how. When I first started playing gigs I was stoked to get two free drinks and find a five dollar bill in the tip jar, but it doesn't have to be like this...If you do one or two of these things well, you can make money playing music for a living.
Join a cover band who plays on cruise ships. Luxury cruise ships are a rapidly growing industry which have a high demand for entertainment. These cruise ships can afford to pay musicians up to 10 grand each for a four month job. The food and board is accommodated as well. Travel the world and make a boat load of money. The amount of jobs for cover bands at local clubs is few and far between, so playing cruise ships is the way to go. Search on craigslist.org and keep your eyes open for these cruise ship jobs.
Be prepared to market yourself. If you are a singer/songwriter and you plan on making money off of your music, you have to treat music like a full time job. Create a professional website with quality photos, recordings, a press pack, good reviews, and a bio. Hire somebody to get your website to the top of google for certain searches. Some examples are "San Diego Local bands" or "best new music LA". Sticker and flier up the town, and play open mikes frequently. Whenever you play a gig or an open mike say your group name at least two times every 15 minutes. Look like a rock star, and always have your cd handy to sell. Network with everybody, and if you're not playing gigs in LA or New York, you should start.
Teach lessons for the instrument you play. This also involves having a sold marketing plan and a good sense for business. Advertise on craigslist and other free sites like this. Get car magnets and t-shirts with your business name and a phone number on them. Your business name could just be your name, plus what instrument you teach. For example "Steve Brown Drum Lessons" or "Michelle Davis Guitar Lessons". Do research on what people charge in your area and either match it, or just lower your price by 5 bucks. Teaching lessons has been my number one source of income for a long time and it's a really fun job!