Compose a beat. Hip hop is music that is formulated around rhythm. Making a beat can be done by manually composing a rhythm using recording equipment such as a keyboard with track making capability. Another way is to beat box the rhythm to yourself until you produce a beat. Either way the beat is the foundation of your hip hop song.
Formulate a theme for the song. Your song needs to be about something. Many popular hip hop artists use political, cultural, and day-to-day topics in their songs. Incorporate the theme into the music and lyrics of your song.
Brainstorm lyrics to the composed beat. This requires that you listen to the beat intently at least once so you will have some idea where to add the parts of your song. When listening to the beat try to think of a snazzy hook (chorus) to go with the song, and where you would like it to be in the song. You will also want to think about how many verses you want to write. This is not the final draft of the song so ideas can be written or memorized as incomplete thoughts.
Be original. Add your own style through the lyrics or music and try to incorporate it as much as possible. Remember that although this is a hip hop genre song, it is still a song that you are composing and it should express that. Originality is a highly touted characteristic in hip hop music and its culture. Finding a way to be different, but not so different that you alienate the genre's base will help your song's popularity as well as the creative process.
Refine your lyrics. After you have composed the foundation of the song through beat, theme, and lyric, it is time to start putting the pieces of this puzzle together. Now is the time to completely express your theme through composition of your lyrics. Test the lyrics by speaking them to the beat and see if they fit with the rhythm smoothly. If they do not then further revision of the song may be necessary. Practice your song to portray the image that you know your lyrics as it will translate during recording. Stumbling through lyrics or parts of the song will seem tacky and turn off the audience, as it may sound amateur.
Lay down the final recording or do a final run-through. If you have voice-recording technology this is the time to perform your song and record it as it is to be performed. Start by recording the hook (chorus) in your hip hop song. After you have done this it will be easier to perform and record your verses. In the case you do not have recording equipment available, focus on the live performance. You can achieve this by simply practicing the song with the music until it becomes second nature to you.