It is posted in many languages with clear pictures so this really will help you to understand te process easily.
This process can be done with any type of reactive dye likeTobasign, Drimarene-K or Procion MX
This what I did:
With my stock of 10% dye-concentrate (10 grams of Procion MX powder to 100 ml. of water), I painted my cotton swatches on my covered table. There is NO soda-ash involved in this stage. I repeat: NO Soda-ash Yet. Just painting dyes.