Well, the thing here is, GMK dark was designed by someone and you would first have to ask the OG designer for permission. It's pretty uncommon for a set to be run by someone that isn't the designer, the set is usually just never run ever again unless it's really popular and the designer is still active. But if you did get permission, you would then make kitting, renders, and write up an IC.
Should the IC do well, you'd then contact vendors to run the set, you'd then settle on a GB date which then your vendors will do most of the contact work with GMK.