I use a striking board. That has been the method most fitters have used over the last 10-15 years. It works quite well as it shows you the dynamic lie angle.

1. Initial fitting is static, based on a static setup with club.
2. Next step is to adjust lie angle based on active dynamic swing. Lie board and impact tape on sole of club work best. Adjust lie angle to get impact in middle of the sole of the club.
3. Always remember that "club head droop" affects the lie angle and the more flexible the shaft, the more the club head will droop. So if you change flex on shaft, you'll need to adjust the lie angle again.

I usually start with a 6 or 7 iron and get that club perfectly adjusted. Than you build up and down a set from there. Only minor "tweaks" will be required. (1/4 degree of lie angle or less) Making sure loft of club is correct is an ongoing process with the lie angle adjustment. If your clubs are "cast" clubs you can adjust them only one time. If you attempt more than one adjustment the hosel of the club becomes like a paper clip you bend back and forth. You run the risk of snapping the hosel.