wooow that sounds awsome! may i offer a few tips for ya?
oks 1).write some of the major stuff down on paper (trust me it works!)
2). start building the plot (if not done aready)
3.) draw the characters on paper first (this what i do^^ it helps me visualize what the finished chacter(s) are going to look like)
i hope ,this helps you a little ^^;;