Compose or acquire a beat. When writing a song, the lyrics must flow with the beat. If you write a song before listening to the beat, the lyrics may not match with it. Go to a beat website such as 20 Dollar Beats (see Reference section). Browse the selections and click "Play" to preview and "Buy" to purchase a track.
Listen to the beat. Repeat the track so that you can catch the rhythm. Hum along to the beat as you listen. This will create a flow that you will use to write your lyrics.
Create a theme or song idea. Some topics include love, money, struggle or war, depending on the melody of the beat. Write a list of several song ideas. Continue to listen to the beat and choose the topic that best suits the music.
Write the first verse. A common length for hip-hop verses is 20 to 40 "bars" or lines. For R&B verses, 10 to 20 lines is common. These can also be broken into stanzas of five lines depending on the beat. Create a rhyme scheme such as rhyming every line, every other line, or multiple syllables of several words in each line as well.
Write a chorus. This is the most memorable section and should be the essence of the song. Choruses are often five to 10 lines long and can be repeated several times. Think of the chorus as the foundation of the song, while the verses are support structures.
Compose a second and third verse. Repeat the chorus at the end of each verse.
Write a bridge. This is often the most emotional section of the song and is about as long as the chorus. This is inserted before or after the last verse. After the bridge, the final chorus kicks in and can end with an outro. Outros are bits and pieces of the chorus that are said as the volume fades.