You provide me with the following:
1. A of your track. An mp3 is OK, but WAV or AIFF is preferred.
2. A of the part or parts you would like. If you don’t know exactly what you want, I can be creative.
3. A of the song. A simple chord chart is fine. Also, please tell me the BPM if you are on a grid.
What I do:
1. I send you an mp3 of a mix with guitar parts added.
2. Once you have given your approval, the individual tracks are posted to an ftp site or mailed to you on a disc.