Have you got a manual?
if not I hazard a guess. First set the point gap when the points are at their widest setting, dont ask me what the gap is on your bike but if you dont know set it to 15 thou of an inch or the metric eqyivalent of that.
Now look at your magneto rotor, can you see two lines scribed on it? well the left line will be your static timing line and the one on the right will be TDC (top dead centre)
Now there will be a line somewhere on the crankcase too so if you cant see it remove the spark plug and place the end of a pencil into the plug hole and using the pencil as a guide turn the flywheel until TDC (the piston is at the top) and now look at the lines you will see the right hand line aligns with a line on the case.
Now turn the rotor until the left line aligns and slacken the points base clamping screw (not the one to adjust the gap) place a cigarette paper between the points so thet is gripped, then turn the points assembly clockwise and pull very gently on the paper. as the pints heel hits the cam and the points begin to open the paper will be released ...hold it there and tighten the base plate back up.
That is the crudest way to do it without any special tools and it is how I remember doing it many many years ago so I hope ididnt miss anything.