How much do I need?

Many times I am in the fabric store and see a piece of fabric that appeals to me. I wonder much fabric is needed to make a particular garment.

In my current pattern drafting class, we were told to purchase the fabric. Without seeing or mocking the layout of the pieces; it is difficult to figure out how much fabric to purchase.

By the end of the project, I hope to have a reasonable idea how much fabric is needed to make a sleeveless aline dress. I will gather, average  and post information found on the back of pattern envelopes.