Step 13: First steps 3 - plan your lengths
Make sure you get your overlaps right. I found that the margin between the seam and the edge of the fabric was about right, making an overlap of about 8 inches. The manufacturers say a 3 inch overlap is enough - but I found the slippery quilt slides around a lot, and a 3" overlap soon becomes an 'oh, whoops, it doesn't quite reach'.
Make sure all joints of fabric are where you can get at them. I didn't.
Try not to make cuts longer than they have to be. A cut more than a foot or so is only going to waste fabric: you're better off making a slightly larger overlap at the other side.
Consider using short lengths: they are more manageable. On the other hand, joints are tiresome and waste fabric.
Start nailing from the top: let gravity stretch the fabric for you. Otherwise you're pulling against it. You will want to keep the fabric taut in two directions in any case - three is impossible.