Hi Martinemj, I plan to use a home made Tyrolean mix with a flicker gun to cover a block wall, with an idea to add colouring. Can anyone advise me about the type of sand I should use and type of colouring I could use? Do I need to water proof this also? I can not use a ready mix because It is not available in the country I plan to use it and I would not pay the prices they ask anyway. Any tips would be most helpful as I have a lot of wall to cover. Many thanks, Lawrence.