Guilds in GW2 are cross server/world with an initial maximum capacity of 100 players. Guild capacity can be upgrade via the Guild Registrar by applying for a larger guild license. Each character may join multiple guilds but may only represent one guild at a time.

Creating a guild is a snap. Simply open the guild panel via pressing G or access it from the top left bar. Alternatively, you can go to a Guild Registrar. You can then press the Ceate Guild button to enter a name and tag (abbreviation) for your guild. Note that you will need 1 silver to create a guild.