Decide whether you want to create computer-generated beats, DJ-spun beats or drum beats. Each style has a different aesthetic and leads to a different type of rap. As discussed in the Vibe History of Hip Hop, newer artists like Eminem use computer-generated beats, while “old school” artists like Run DMC and Public Enemy rely more on the record spinning and scratching used by DJs. Alternative artists such as The Roots use live drums for their beats.
Establish the main rhythm line. As outlined in Gotta Get Signed: How to Become a Hip-Hop Producer, this is typically a deeper bass drum or bass guitar line, though many successful songs have been built around tinnier rhythm line sounds such as snares or cymbals. The rhythm line will determine the speed or meter of your song.
Embellish your main rhythm line with several similar sounds. You do not need to have each sound occur simultaneously with the main beat, but each sound should happen in a steady pattern in relation to the main beat.
Add melodic elements to your song. These are nonrhythmic sounds such as guitars or horns. These represent the element of your song that will get stuck in the heads of the listeners. Unlike pop and rock songs, melody usually plays a minor role compared to rhythm in rap music and sometimes is nonexistent, making the incorporation of melody entirely optional.
Write lyrics for your song. Lyrics are unique in that they can follow the rhythm or the melody of the song depending upon your artistic choices. According to Flocabulary, "multi-syllable rhyme patterns are now being used in hip-hop more and more frequently as lyricists constantly try to outdo each other." Such "multis" and other rhyme patterns must be consistent with the main rhythm you have already established.
Develop a lyrical and musical bridge for your song. The bridge is typically the element of the song that lyrically looks back on previous lines and musically introduces a variation of the underlying rhythm or melody of the song.