I tried this techniques a few times with no success. I watched many many films and instructions and they still didn't help. I have to admit that achieving this design is quite toilsome and you have to bear in mind that many things can go wrong and you will have to start over. Anyway I think that the final effect was worth the 2h of 'work'. I filmed a tutorial because it will be easier to recreate this effect seeing it in progress. I just want to add that I am not an expert of any kind, I was just having fun. I know that there are people who are brilliant at this.