how do i get free aim on my sidekick slide when my phone is not pre paid ?

[Mrs.Castillo61510]

so my phone has unlimited text & calls & is not pre paid so how do i get my aim going on my sidekick slide?,& yes ive already tried the texting aim thing but for some reason its blocked on my phone,ive heard of the code but i heard that you have to have a pre paid phone but im wondering if i kan have the code while i still have my unlimiting text & calls // I NEED HELP PLEESE