Another technique I use when dyeing cloth is 'Donut' Shibori. It was taken from a brilliant book called Shibori for Textile Artists by Janice Gunner. Take a length of fabric, not too big as the dye needs to penetrate to the centre, and some string a little longer than the width of the fabric.
Roll the fabric round the string fairly tightly leaving some string poking out at the ends.
Gather the fabric tightly into a donut and tie the ends of the string. Put into dye and leave at least a couple of hours.