If you are in a rush to leave, you can also do this: Since you are GM, go to the guild page and where it says "Open Admission" put a check next to it. Set the level requirement to something really low. Give it some time, maybe an hour or something, and someone will join your guild automatically. Once you see someone is in, you can automatically transfer GM over to them and hightail it out of town.
Obviously, you only do this if you do not care at all what happens to your guild.