first mix the ingredients for the mango layer on lowest speed and then another 20-30 seconds on highest speed. Add more water if the mixer is "complaining"
fill in two glasses
now mix the ingredients for the second layer in the same manner (add a bit of water if needed) and fill carefully into the glasses by using a tablespoon. Hold the spoon into the glass and pout the smoothie over it. That way you avoid the two layers mixing up.
If you want to use fresh fruits, add ice cubes. The smoothie tastes better cold and gets a nicer consistency