ggibby:


First, here's how the calculations basically go.
The smaller your pleats, the more fabric you'll use.
Your aprons are using up 32", but theres more to allow for than just those. You need about 36" for the apron side hems and assorted fiddling. That's got you down to 184" left out of your original 7 yards. I'm assuming you've got about a 44 inch waist, which leaves you with 28 inches to cover with your pleats.

With a 1" pleat, you'll have to do [28/1]= 28 of them, and that will use up [28 * [6"sett+1"advance]] = 196" which is more than you have left.
So you know that they've got to be at least a little bit larger than 1", or you'll run out of fabric.
At 1.5" pleats, you'll use [28/1.5]~19 pleats, and [19 * [6+1.5]]= 142.5" of fabric, which will work.


You'll find that your tartan has some natural 'break' points in the repeat. Say your pattern repeats every 6 inches. Try taking some chalk and dividing one 'square' up in different ways.
Try 3 2" divisions; try 6 1" divisions; try 4 1.5" divisions. This will give you an idea of how each will look. Pick the style you like and play with it a little bit.
See if you can make divisions that are equal but that line up nicely with the pattern of the kilt [to help you do each one right and consistant].

Now once you decide on that, it's time to pleat. I know that this isn't how it's always done, but I press my pleats [with a press cloth] BEFORE I sew them. That way I can make sure that things look okay, and it really helps to keep your stitching straight.

You know what? I'm just going to send you to
Here
and here
, so let me know if you have more questions.