One of the most common jobs playing music is playing as part of an ensemble or band. Depending on your town, as well as your ability to travel, there might be many opportunities to perform live and make money. Bands and ensembles come in a variety of forms and sizes. For example, you don't have to play rock band instruments to be in a profitable music ensemble. Whatever your instrument, there's a good chance it could fit in some kind of music ensemble that helps you make money.
Commercials often employ background music or theme music. Someone has to play those instruments. Many musicians can make a profitable living by recording music for jingles. Some write the music, while others simply perform on the recording. This can give you an opportunity to play a wide variety of music styles. Plus, it gives you a chance to hear yourself playing over a commercial or other advertisement on television or the Internet.
Weddings frequently feature music and can be very profitable for musicians. While DJs are often used to supply music for wedding receptions, many couples are still hiring bands to provide a lively atmosphere. Likewise, other musicians can get work providing music during the wedding ceremony itself. This can help add a magical touch to a wedding. Importantly, weddings are often attended by large amounts of people, exposing you to a lot of potential work if others are impressed with your playing.
Many churches have live music during their services and you don't have to be an organ or piano player. Some churches have entire bands that can count on work every Sunday or whenever a service is held. Likewise, many churches hire musician for special services, such as Christmas and Easter. Similar to weddings, playing at churches can expose you to people who might be interested in hiring your services.