i was doing texturing with reference tutorial by kris kosta…and this is where the problem occurred
i did everything as he said…
but when i press pick now… all the texture disappears… 
don’t know whats going wrong
The demo head doesn’t have UV’s.
Go to level 1 and click the Tool>Texture>Enable UV’s button. Then assign a blank texture to your model that is the size of the texture you want to paint. Press Tool>Texture>GUVTiles to assign UV’s, then return to the highest level and continue with the tutorial.