The difference of ranks determines handicap.
If you are a newbie: Assume your initial rank is between 30 and 20 kyu.
How to adjust your initial rank? Challenge other players!
- You have won a game against a player, who claimed to have a stronger rank than you? Fine! Adjust your rank. Step by step.
- You have lost a game against a player, who has a weaker rank than you? Please lower your rank. Step by step.
The method to adjust your rank is: Challenge other players with acknowledged ranks. And adjust your (local) rank. (As soon as you get the result of that game.)
Discover and communicate (!) your real (!) level of Go experience to your next (!) opponent. (As fairly as you are able to.)
See rank - worldwide comparison for local differences of rank systems.