My son turned 14 the other day (where on earth has that time gone?!) As he's a very keen guitarist & loves rock music, Inkadinkado's Rockstar stamp set is perfect and was bought with him in mind. But when I came to make the card I was short of inspiration until I saw this card which was based on a sketch.
The backing paper was made with a combination of inks & various masks and stamps. The main image was stamped in Brilliance Pearlescent Poppy then clear embossed. Charms wouldn't normally be appropriate for a teenage boy but this one came from a set by Crafty Bitz which has a few good ones for rock music-themed cards.
Cardstock: Bazzill, Xerox Colotech Plus
Main image stamps: Inkadinkado Rockstar #98693
Inks: Brilliance Pearlescent Poppy, Versacolor Charcoal, Versafine Onyx Black
Charm: Crafty Bitz MT165