This, duh, is your zero-mark. Remember where this is. This is where that friend comes in handy, one to do the moving and one to do the looking. When it's set, tighten everything back up and shut the motor off before you remove the jumper. This is an obvious modification, but one many people don't do because they don't have timing lights.
Timing is advanced by rotating the distributor.
The distributor is held in place by 3 bolts. Do this while the engine still retains a little heat from driving as it will make it easier to loosen the bolts. Wait a while though or you'll get burned. If there isn't one, make on. Now loosen up the distributor and rotate it counterclockwise to the first mark.