To adjust the initial timing, a timing light is sufficient. In theory, in 95% of cases, the engine will then start. At the very least, it should start with this setting. The adjustment value (if I remember correctly) is 0.7 +/- 0.02. HOWEVER: There are risks and side effects, so be sure to read the 'megakaltstartthread' by haehlein!
In my opinion, the timing advance should only be adjusted dynamically (i.e., using a VAG-COM or an original VAG tester) for it to be meaningful and reasonable.