At the beginning you will realize that it is not that easy, and that it is very easy to put a little bit everywhere badly distributed vs a thin regular layer.
Especially if you go fast enough (with a spoon for example), the best way to make small piles of powder badly distributed on the targeted surface.
The use of a
sieve or a
sprinkler, which I have
already mentioned, is almost indispensable in practice, as it contains the powder to be spread evenly and allows it to be spread "in the rain", thus sprinkling.
But, in a very natural reflex you will probably do this:
It works of course, but you will probably put it far beyond the targeted surface, for example far beyond your pie.
The practical trick is to block the colander with your hand when it reaches the limit of the right surface.
So you take a little momentum to the right (green arrow), and you go to the left where your hand blocks the colander (red arrow) with a tiny shock against your hand, a shock that still helps the sprinkling.
Of course, if you are left-handed, you will reverse the direction.
It is a very simple and effective gesture, try it the next time you have to sprinkle.