The biggest conference problems appear in the final weeks, but their causes are planted in the first. These decisions should be settled early.
Goal and audience
Why is the conference being held, and who must attend? Every later decision on programme, venue and marketing traces back to these two questions.
Programme and speakers
Fix the themes before the names, then give each session a chair, written content and a deadline for materials.
Venue and flows
Test visitor movement on the floor plan, not just on paper: registration, halls, breaks, exits.
Sponsors and exhibitors
Packages and mutual commitments are written before they are announced and tied to a clear delivery schedule.
Technology and production
Sound, lighting, screens and streaming need a full rehearsal; testing each element alone is not enough.
Contingency and documentation
A fallback plan for speakers, technology and weather where relevant, with an owner for each item. After the event: a short report on what worked and what to change.
A good conference looks easy to the attendee because all the difficulty was settled behind the stage before it began.