1 DAY IN ADVANCE
Bake and cool guitar pan cake. Cake is one layer, 2 in. high. Use knife and pattern to trim neck of guitar into a point for end of tie. Trim top of guitar neck level with body.
Prepare buttercream icing following recipe directions. Tint portions of icing brown/red-red combination (for brown), copper (for skin tone shown), black, light red-red and light sky blue. Reserve remaining white. Use spatula to ice cake sides, neck of guitar and background areas smooth. Use toothpick and pattern to mark tie area on cake.