When and how to add supers is one of those subjects over which beekeepers will argue for hours.
Here are my thoughts and the techniques that have done well by me over the years.
First: try not to add supers too early. Make sure that the brood box is nearly full before adding the first and then try not to add more until they are close to filling the existing one. this of course requires regular inspections to check how they are getting on.
Then there is the subject of under or over supering. I have always operated as follows:
Where the flow is strong I under super as bees do not like an interruption in their stores and under supering will encourage them to fill the gap. Where they have a good flow this should not be a problem as nectar will be coming in fast. If the flow is less good or intermittent then I over super.
I check my supers regularly and if the bees are only building in the centre of the super then I will move the full frames to the edge and the empty ones to the middle to encourage them to fill the super before they get another.
I hope this article is helpful and may all your supers be full ones.