The two main things you will need are:
1, Some form of dividing head - a method of rotationg the gear blank a set amount, each increment will be one gear tooth. These are easily available from
model engineering suppliesbut you could make something up with a 360degree protractor, center pivot and some method of locking the work at intervals.
2, A method of moving a gear tooth cutter across the edge of the blank or advancing the blank into the cutter, something usually done on a milling machine but could be sorted on a router table.
Depending on the size of the gear you could get away with a scroll saw and a bit of fettling if the mesh is not too critical, print out a template on the computer and stick it to the wood.
Jason