I used to do a lot of dressmaking too, years ago before VAT was added to everything and doubled the price.

My only suggestion would be to buy a pattern and then lay it out on a plan of 36" material. You could measure out an area 36" wide on the floor perhaps. Don't forget you need left and right sleeves etc. so the material has to be folded in half either lengthways or widthways, and allow extra material for nap so front and back each lay in the same direction.

Good Luck