Hi Medyo,
just like a dizzy in an old car!
put a degree wheel on the other end of crank ,
find TDC by piston for no 1. cyl .on compression ( both tappets loose)
turn the crank forward until the desired degrees ( either or idle say 10 or max advance say 36 deg) mark the spot.
Install the drive and dizzy with rotor button pointing to no 1 cyl lead and the points just opening , use 12 volt light or cig paper or listen for spark crack at points to find the sweet spot.
Unless you know the advance curve etc it is probably easier to set the up to have points just opening at idle deg say 10 deg BTDC, also mark the max spark advance point say 36 degrees you want on the pulley drive somewhere so you can use a strobe to check max deg advance when its running.
Hell Medyo that sounds confusing doesnt it
.....pay some bloke $50 to do it , watch and learn
have fun mate.
ciao