At some point in everyone's life they want to be a major rock star. It might be after they go to their favorite bands concert, or when their parents buy them a small version of a guitar, or maybe a mini drum set. Some kid's take that dream farther as they grow up, and they begin to look at music as a career, and not just a hobby. But most people underestimate how hard it is to break into the music business. It takes years of training, playing out, experimenting with sound, and kissing up to every person connected to music that you meet.
First, you need to develop your sound. I would recommend that you develop a personal style before you start playing with a band, if that's what you choose to do. You should be able to put on a great show with just you and your instrument on the stage before you start playing with other people. Even if you're a bassist or drummer, who many consider to be a less important part of the band then lead singer or guitarist, you need to be able to play like you are the most important part of the band.
Then, you need to find a band to play with, if you choose to. You can try to make it solo, but this is usually just a path that singers who play guitar take. It is a lot more difficult to break into the music business if you're a bassist without a band then if you're a bassist in an amazing band. But don't assume that your band could play the Super Bowl after one practice. It will take months of practice together before you can play well enough for your first gig.
Once you make it to your first gig, show up early, be polite, and always get it in writing. Make sure you have a contract between the financial leader of the band and whoever has employed your band. You can often get into trouble when it comes time for payment if you don't have something that specifies what you're getting paid and when signed by both parties. But be polite about it when you are asking to get a contract signed, and when you are collecting your pay. Be polite, but firm. Be sure not to let them push you around, or you won't get taken seriously.
The more you gig, the more experience you get. Don't start playing out to early, but once you get comfortable together, play at least two gigs a month. This will help your confidence as a band, and give you the experience of playing together in front of a crowd. Book as many gigs as you can, but don't play for free. If people want your services, they should have to pay for them just like they would for a caterer, or party planner. Weddings are an excellent place for a band to start playing, but if you want to be an original band who doesn't play covers, that's not going to be a good place to try to advertise.
Don't be afraid to be original. Just because you think that every mainstream band sounds the same doesn't mean that's what the record companies are looking for. Be original to get noticed, and don't compromise your music if you get noticed. If a record company wants you to change the way you play your music before they sign you, they don't want your music. But once you do get noticed, but prompt, polite, and learn to take constructive criticism. If a record executive tells you that he likes your music, but maybe you should try doing something different with one of your guitar solos, try it. Offering opinion isn't the same as trying to change your music. Who knows, you might like his idea.