LOL, I didn't mean to offend. Do you have a trouble shooting thread? or perhaps a Q/A thread? Because I can't seem to find the answer ( and there were a couple of other confused peeps like me) in any related topic.
Should be relatively easy for the guilds. have the right tech, be in Guild civic, have the appropriate GP for the guild. Problem is, I can't even build the Master Servants guild to even start any other guild.
Don't get me wrong, the mod is one of my favorites, but it's just a wee bit frustrating when you can't find the answer to your questions.
TBH its been so long since i modmodded ROM, so I cant remember it all, but I do recall it had to be changed, coz there was only 1 resource spot left and my guilds used 3 different types of Guild Papers.
But in short :
Each Civilization can found 3 Guilds but only 1 from each Masterclass (Servants, Victualliers, Craftsmans)
(this is to avoid hogging where 1 civ gets em all, and to avoid a bug in worker AI, where Guild Masters will replace already spreaded Guilds)
To found a Guild you need the Master Guild HQ (Serv, Vict, Craft) built in a non government center city (i.e. No palace, Forbidden City, Versailles) coz each Master Guild HQ works as a gov center itself.
The Master Guild HQs provide each their own Guild Charter (resource) which is being used by the different guilds same way sids sushi uses rice f.ex.
(this is to prevent to Guilds of same Masterclass can be in the same city)
Then you need the right Great Person, and the building requirements for each specific Guild. F.ex. you will need a couple of Fishing Villages if you want to found Fishmongers Guild, or theatres if its Artist Guild or Butcheries if its Butchers Guild.
So... if you f.ex. wants to build Masons Guild, then you need to build MasterCraftsmans Guild in a non gov center city. Then you build at least 3 walls (on Large size map) and use an Great Engineer to found the Masons Guild HQ.
But... tbh I think it wasnt very finished in ROM, so if you want to give it a try I recommend my own mod (which is far more stable, less memory consuming and... slightly unfinished

) It plays well up until industrial.