If you are planning on making major changes to a dress (adding sleeves, changing illusion net from nude to white, adding a large amount of beading or lace) plan to do a first fitting or consultation at least 4 months in advance. The work may not take that long, but time is required to obtain the materials needed for the build. Make sure to speak with the store where you purchased the gown about a major change. Some fabrics, lace, etc. need several months to be ordered from the designer so it matches the gown.