Summarize this article in one sentence.
Here, contestants have to freestyle over a beat selected by the DJ and you'll be timed, so you won't be given much time to think before you've got to start rhyming. If you want to battle, you'll also have another MC across from you who may be more experienced and eager to embarrass you with crude diss lines to get cheers from the audience. This is one of the most exciting parts of the rap game, but you'll need to develop thick skin and considerable skills before trying this in public. It's a good idea to attend a lot of competitions before attempting to compete in any of them. Get a good feel for your skills and the skills of the other competitors before jumping on stage. try to get in touch with some up-and-coming producers in your area or online to provide you with some original beats to work with. If you have a beat, making hip-hop music requires little more than the most basic audio editing software and a microphone. Attending shows, competitions, and battles is a great opportunity to meet other rappers and beatmakers you might collaborate with, or who might have resources to share with you. If you eventually get enough material that you're proud of, start a YouTube channel for your music and start sharing your music across social media. Put a mixtape together and release it for free on the Internet. Increasingly, rappers who get signed to big contracts generate publicity and buzz by releasing free mixtapes. Burn CD-R copies of your music and give it out at concerts or gatherings with your contact information included on it. Keep beats on your phone or iPod, and freestyle inside your head while doing every day things like walking down the street, taking the bus or train, or grocery shopping. The more you practice your rhymes, the better they'll get.

Summary:
Check out a freestyle competition or a rap battle. Make original music. Put your music online. Keep practicing.