In Oslo we do it the easy way
We determine the minute of last landing/Departure and who this will be. (Normally time for change is set 20 minutes after TWR inform us we need to change RWY)
Then we just hold at start point of STAR for 10 minutes (little depending on the lenght of the STAR) and start arrivals into the new runways at normal rate. This way we will have first landing on new RWY at about 20trackmiles from Touchdown when last opposite departure is airborne..with the arrival "pressure" up again to normal from first landing.
In low traffic periods, we do it more manually and find a good time in traffic to do it with some delaying vectors on the innbounds.
However the "fun" starts on the days you have to make instant changes due to rapid windchange from CB's and so on
Then we will normally have planes on vectors everywhere in a controlled caos
