Here is another variation of the dhamala turban without the Chand Tora. Each person adopts their own method of tying the dhamala. Once you learn the basics you can tweak the method to fit you.
Damallas definitely vary in width and length. The pieces I used were:
one 5 meter piece (Dark Blue)
one 11 meter piece (White or Blue or any color, this piece has a knot at the end to hold it on my head in the beginning)
Both pieces are about 35 cm wide, and referred to in Amritsar as Damalla Material. I'm not sure of the official name of it.
The difficulty with tying a Damala is usually in getting the shape right. It may take a good 5-10 tries of tying practice to get the right shape.