Cedar makes great signs, especially if they'll be outside. You can practice with poplar, pine, or any cheap wood you can find. Pallet wood also. That is usually free.
1/4" Core box bits,
http://www.mlcswoodworking.com/shops...s/bt_core.html
1/8" and 1/4" straight bits work good.
Make a large base for the router out of plexiglass so the router has a firm base and won't tip on you.