The kilt worn in the movie "Braveheart" is called the feile mor in Gaelic, or great kilt. It's fashioned from one long piece of cloth and serves not just as a Scottish Highlander's clothing but a hood to protect him from the elements and a blanket to sleep on at night. The plaid in the fabric, called tartan, was developed after the great kilt and was used to identify a Scot's clan and as a camouflage in battle. Gathering enough wool to create a great kilt often took a year and then it would take several weeks to weave into the kilt fabric.
Purchase woollen cloth with a plaid pattern. If you want to be truly authentic, research your Irish or Scottish ancestors' clan colours and pattern, called a tartan. The fabric should be 9 yards long by 30 inches wide; this is actually the origin of the phrase "the whole nine yards."
Cut the fabric in half using scissors so that both pieces are 4 1/2 yards by 30 inches.
Lay the two pieces on top of each with the right sides together.
Sew a seam using needle and thread along the 4 1/2 yard side. When you open the fabric it will be 4 1/2 yards long and 60 inches wide. These are the generally accepted dimensions, although a Scot of a larger girth might need up to 6 or 7 yards of fabric. The hem should fall at about mid-knee.
Sew pleats into the portion of the great kilt that falls below your waist, or pleat the grand kilt every time you put it on.