The order of ingredients doesn’t really matter. Main thing is to let the chia seeds soak in the milk for a few minutes so they start to soften. You could make this the night before and leave it in the fridge minus the ice cubes of course, you may need more milk or water as the chia seeds will absorb a lot of the liquid. I make mine pre-workout (about an hour before I have it) so espresso has time to cool and chia seeds can do their thing.