Decide to make a full size replica of the Guitar Hero II guitar in cake form. Spend the next few weeks freaking out and searching for instructions on fondant icing and cake decorating!
Pick up bits and pieces for making the cake over the course of the month... spending over $100 just on "stuff". For me this meant buying icing, a rolling pin, a rolling mat, palette knives, an icing smoother, cake board. Luckily I already had bowls, a mixer and a few bottles of wine in the cupboard.
Step 1: Get started with the fiddly bits
Cut out templates for the cake (I used the actual guitar to make my template) and start making the "extra" pieces by rolling out coloured icing and cutting to size. Put these in an airtight container to harden.