I've finished all 6 nebulas and they start going on tour with the kids club from tomorrow. More photos on picasa:
I'd start off by tye dying the sheet a base colour, such as green or blue, three hours later I lay it out flat on some plastic sheeting. Onto the spray bottles: two bottles filled with colours (silk dye, bought as a liquid) and one filled with water to blend the colours. I used an image as reference per image so I had something to work from, and once the intial pattern was 'painted' I'd work more colours on top with different intensities of dilution, or using dylon powder dye in the bottles - mixed with salt and using hot water.
The silk dyes are very intense when used 100% and leave the fabric soft to touch, whereas the dylon can be used to cover larger areas and leaves the fabric more crunchy due to the salt.
Once nearly dry (the next day) I sprayed or splattered some areas with bleach, or left to dry completely before applying a second lot of dye. Onto the ironing which would take about 45 mins per sheet to ensure the silk dye is fixed, and because the sheets are huge! I'd then lay
them out to map the sequin using dressmakers tape and sew sew sew!