my car with timing at 10*

1. Buy or get a timing light
2. Have a 1/2 inch wrench ready
3. Open hood
4. Loosen distributor hold down bolt with wrench, but don't turn it yet
5. Hook up timing light to #1 spark plug wire and battary
6. Stark engine
7. Open EST wire (pull spout connector located under air intake)
8. Shine timing light to harmonic balancer (when light flashes, a pointer will be pointing to the degrees BTDC
9. Turn distributor to change timing to your needs
10. Put spout back in (try not to move distributor)
11. Turn off engine
12. Tighten hold down bolt
13. Unhook timing light
14. Close hood

Make sure you do step # 3, that is the most important step
 
IMO its better to tighten the hold down bolt for the dist before you turn off the car and plug in the spout. This way you can shine the timing light on the harmonic balancer while the car is still running and make sure you have the timing set where you want it. Sometimes the dist will move as soon as you take your hand off of it so I like to make sure and tighten it right away before it has a chance to move.
 
Oh yeah that makes sense. But I use a 1/2 wrench that is shaped like an L that helps make tightening that bolt easier while the car is running. Either way will work but just make sure and double check after you have tightened it that it didnt move.