Hold your finger over No.1 plug hole have somebody bump the starter. When you feel air stop I've missed and had to do it over. Anyway rotate the crankshaft until you are at zero degrees. Back if you feel you passed it or forward. After you do it a few times its easier. Next find No.1 sparkplug hole and set it this way after you reinstall the distributor. Usually you may have to rotate the distributor slightly as somebody is trying to start the vehicle.
Then follow the manual and use a timing light and set the timing.
Its easier than you think just stay relaxed.