Is your top squared- same length on both sides, same width across top, middle, and bottom. You will need to make a sandwich of batting between top and bottom. Do you have space to sprawl? Ideally, you can find some big banquet tables to work on. Clamp or tape layers down, smoothing out wrinkles as you go. This can be basted, pinned, glued, or tied to stay together. Will this be a tied quilt? Machine or hand quilted?
The search function above will let you explore the different choices.
Have fun!