Brainstorm a list of words you want to use in your song. If you want to create a list of rhyming words, first decide which words you want to rhyme with. Write down your list in a notebook to keep yourself organized.
Start with one word. Listen to the last syllable of the word. That is the part of the word you use to rhyme. For example, if the word is "bullfrog," the last syllable is "frog."
Remove the beginning consonants from the last syllable. In the previous example, you are left with "og." That is the sound you rhyme with.
Go through the alphabet systematically. Add a consonant to the beginning of the syllable. For example, the letter "A" does not work but with the letter "B" you make the word "bog." The letter "C" does not work but with the letter "D" you make the word "dog." Continue making words until you make it through all the letters in the alphabet.
Consider combinations of consonants. For example, the blend "bl" makes the word "blog" and the blend "cl" makes the word "clog."
Consult a rhyming dictionary to double-check your work. Add any words to your song list you may have left off.
Repeat the same process for the remainder of the brainstormed words from Step 1. When finished, you have an extensive list of rhyming words and are ready to write your song.