I do all my wood repair at TechShop.
Step 1: Supplies
*Not pictured: the necessary plastic bag
Step 2: Prep
Tape-up the sides and bottom of the piece to keep the resin inside. Cracks run deep, so it is sometimes wise to tape the entire piece inside a plastic bag. Do the repair work before making any cuts or planing on the wood and don't worry about the resin puddling on the outside.