Dress alteration timeline. How many weeks before wedding should i schedule my first alteration appt? How many weeks before wedding should dress be done and all ready to go with no more alterations needed. My brother in law owns a tailor store and a bridal shop and says 4-6 weeks to get first alteration started, this scares me. I guess i want my dress done and ready to go sitting in my closet 4 to 6 weeks before wedding,so i dont