The earliest months are about decisions everything else depends on. Tackle three things in order: budget, guest list, and venue.
Start with an honest budget, who's contributing and how much. That number quietly governs every later choice. Next, draft a rough guest list, because 80 guests and 200 guests are completely different weddings and dictate venue size.
Then book the venue and lock the date. Popular venues fill 12 to 18 months ahead, especially for peak-season Saturdays. With a date secured, reserve any must-have vendors who book early, photographers and bands often vanish first.
Rule of thumb: don't pay a deposit on anything until your budget and guest count are realistic. Reversing those decisions later is expensive and stressful.
