mines set around 6*BTDC. Chiltons manual says anywhere from 4*BTDC-8*BTDC depending on year and auto or manual.
Also could be as high as 10*BTDC for high altitude
As far as the how goes start and warm up the engine to operating temp,
Disconnect and plug vacuum advance at distributor to prevent any distributor vacuum advance, loosen distributor clamp locknut, turn distributor slowly by the base(not the cap) (a little movement goes a long way) retighten locknut and check your progress. Counterclockwise advances timing (towards BTDC) and clockwise retards timing (towards TDC or ATDC)
Once you find your right setting tighten the distributor clamp locknut back down, receck timing to make sure when you tightened the nut you didn't move the distributor, reconnect vacuum advance hose. drive away and go wheel!!!
Hope this helps
If I'm missing anything experts please help out and fill in what I've missed