The AAA – I tend to use this one for more emotional types of songs, especially emotional story-telling kind of songs. I tend to end each verse with a “refrain” that is repeated at the end of each verse to give the listener some familiarity at the end of each verse. This can be a powerful form.
The AABABSB – When I have a little bit of extra story I need to tell before the chorus, I go to this form. The two verses up top let me get the characters, setting and context in place before the listener hears the chorus. After that first chorus, I just have one verse and then it’s choruses from then on with the exception of the instrumental break. Since I have three verses, I don’t like to use a lyrical bridge in this form.
The ABABCB – I use this form when there are loose ends, I still need to tie up after my verses and first two choruses. I use the bridge to try to take the song to another level and “knock it out of the park”. There you have it. I’ve written and demoed more than 6,000 songs and 99.9% are one of those three forms.