For The Best Results:
Before sending your song export every file individually in WAV. or AIFF. format. For example; your lead vocals, chorus and ad libs should be in separate files. The instrumental should also be broken down into individual files. For example; the bassline, synthesizers, piano, kick, snare, etc. should also be in separate files.
Take all effects off of your recording unless you fill that it is essential to the song, like a phaser effect on a quitar. Reverb, compression, etc. should be taken off.
Submitting your files: