This is generally used when someone has done something that requires appreciation, acknowledging or praising.
So for example if a child at school has answered a question correctly the teacher may say ‘clap for him/her’ and the whole class will erupt in clapping. This is where the phrase is used the most. It is also used amongst adults when someone has done something of good note.
It can, though, can be used playfully, well amongst us maybe! For example when said to someone when they have managed to do something well, such as opening a water bag without spilling it (a little extreme but you get the gist!). Likewise if you’ve gone and bought ice-cream for everyone!
So next time someone gets something right, go on give it a go, clap for them. It may make you feel good!
Ochina! x
Laughing Doves 
It should be noted that it is not just any old clap (no pun intended), but a very special kind of clap that has rhythm and movement associated with it, very much a reflection on everything Ghanaian. The clap goes like this:
“clap clap clapclapclap clap” I.e. 2 slow, 3 fast followed by 1 slow.
As Louise says, this can be heard in nearly every school in Ghana. People we work can be seen clapping for themselves from time to time! So don’t be shy, give yourself a clap now and again!