The audio cassette tape will have a piece of paper surrounding the cassette. Take this out and lay it flat. Look through magazines and cut out images you like with an exacto knife. Glue whatever you want onto one side of the cassette paper, layering and juxtaposing images to create whatever meaning you'd like for this mixtape.
Take your permanent marker and doodle and write over the collage. You might want to write a quote, the name of the mixtape or a message for whoever the tape is for. You can also draw doodles and pictures over the collage to make a multi-layered effect.
Flip the cassette paper over to the back side. Using white paper and an exacto-knife, trace and cut out the shape of the cassette paper on the white paper, and glue this onto the un-collaged side. After the glue dries, write down the play list on the cassette. Notes and comments about the different songs can add character to the playlist.
Fit the newly designed mixtape cover into the cassette case and you're done.