When an artist begins their rap career they must go through three phases and a few steps. There are a few phases and steps within each phase.
Phase 1: Writing lyrics and picking the right instrumental
The first step in phase 1 is picking the right instrumental, whether its "gangster", classical rap, hip hop, club, etc. Depending on the lyrics and flow, choosing the right genre in rap is key for a successful track. The second step is the quality of the instrumental and voice. Never rush into things. Use a beat that people bob their heads and like. If you use an instrumental that's not very good the listener's attention span in listening to your music will decrease. Same goes for the voice. If you scream in your microphone and leave your voice distorted, the instrumental can be hot, but people will not like the track because of the bad quality in voice. To fix this issue spend a little more money on a quality microphone. The Samson C01U USB Studio Condenser is a good starter.
Phase 2: Mixtape
Step one: focus on a theme for your mixtape. Basically pick out a name and use an intro to introduce the theme and the outro to conclude your mixtape so people will remember it and / or talk about it. In between you can have any kind of song, just make sure one of the tracks follows the theme. Usually track 2 is the theme song. Step two: do not make your mixtape to long. Eight to twelve songs is the perfect length. Remember a mixtape is not a debut album. Step three: do not make the mistake of having a good mixtape, but crappy self-put-together mixtape. Get a professional to design artwork or do the artwork yourself, but spend some time on it. Use quality paper for the inserts and such. Also, make sure the cds are not just burned and wrote on. Find a company to make real authentic cds. And ALWAYS shrink wrap the cd, it looks better in local stores. Step four: always add the credits to your songs. Make sure you give credits to the producers and featured artists.
Phase 3: Marketing
Step one: use free tools to market your mixtape. Make a music video or just a slideshow and put it up on YouTube. Show the world your talent. Add a link to a website where people can buy your mixtape. Use Craigslist for your local cities (where you perform and such) to promote your shows and mixtape. Last, use social media like Facebook, Twitter, and MySpace to promote your mixtape and talent.
Step two: book a few shows around your local city. Performing is a good way to promote your mixtape. Make sure to either hand out or sell your mixtape at the place you perform. There are many bars, clubs, social spots that will let you perform for cheap or free in return for customers.
Step three: Get your own domain and website to promote your music. Stop using sites that let you have a small spot and get your very own entire website. There are free places like weebly.com.
Step four: find a local or online record label that is free and will promote your music on their site. Usually they will add a biography and / or link to your website.
That's it. If you are a good artist these three phases will kick start your rap career and possibly land you a record deal.