Six weeks out: decide the basics
Pick your faction, your region and your realm type: those last two name the megaserver you will play on. Choose an atmosphere and write the one-line motto. Create the guild page now: pages created before launch day carry a founding badge, and a page that has been live for weeks has had time to gather members and confirm its recruiting details.
Set up Discord with a small number of channels rather than a sprawling structure nobody uses. Announcements, general, raid planning, a voice channel or two. You can always add more.
Four weeks out: recruit the core
The core is the fifteen to twenty people who will level together, run the first dungeons and form the first raid. Recruit them now, from friends, the player directory and the Inn. Be clear that the first month is levelling and dungeons, not raiding, so nobody joins expecting a raid on day two.
Add openings to your guild page for the roles you know you will need, and add your schedule even if it is provisional. A page with a schedule gets a schedule score on every profile; a page without one does not.
Two weeks out: plan the first week
Decide how you will handle launch night. Some guilds level in a pack, some split into small groups by zone, some just log in and see who is around. Any of these works if people know which one it is. Agree on a levelling pace: a guild where half the members are at the level cap while the other half are still in the starting zones fragments quickly.
Assign a few people to professions early so the guild is not scrambling for bags, potions and enchants later. Write down who is crafting what and put it in a pinned message.
Launch week: expect queues and be patient
Launch days are busy. Queues, crowded quest areas and competition for every mob are normal, and the guilds that enjoy the week are the ones that expected it. Keep voice channels open for company rather than coordination. Celebrate small things: the first dungeon clear, the first mount, the first member to hit a level milestone.
Post an update on your guild page during launch week. Players who missed the pre-launch rush will be looking for a home, and a guild whose page shows it is alive and levelling together is an easy choice.
The first month: dungeons, gear and the roster
As members reach the level cap at different times, organise dungeon runs for whoever is ready and keep the rest levelling in company. This is when tanks and healers prove themselves and when you learn who shows up. Update the roster tab as people commit to their main characters, and use the role field so you can see your composition at a glance.
Keep recruiting throughout. Some of your core will drift away as the novelty fades; that is normal, and a page that is still recruiting fills the gaps before they hurt.
The first raid: set the target, not the date
Announce the first raid when the roster can support it, not on a date chosen in advance. Being attuned, adequately geared and consistently present matters more than being first. State the requirements plainly on your guild page and in Discord so that everyone knows what “ready” means.
When the night comes, keep it short and keep it kind. The first raid sets the tone for every raid after it. A guild that laughs through its first wipes together has already succeeded at the part that matters most.