Nice that you want to participate in the NSK lead!
The sign-up is organised through the GNSK.
Participation costs €20,- 

Sign-up by using the option called sport climbing.
Do not sign-up for the dinner on Saturday 8th of June, this is a different dinner than the NSK Lead dinner.
The party is a 15 minute bike trip, or 30 minutes by public transport, or a 45 minutes walk.

The form is here.

Every city has a guaranteed sport for 3 men and 3 woman. More spots are available and will be assigned based on sign-up time.