How to wire alarm contacts on a triple 3060 window

[J3rm]

I have a new addition being adding to my home and the windows are a little non traditional, as least compared to the rest of the house...
 
One is three windows in one whole/frame
 
So the two on the outside, I can wire contact too and the wires will be out of the way  but the one in the middle I'm a little curious how is the best place to place the wires, so there are not wires all over the frame.
 
we also have some encasement windows upstairs but i was planning on putting the contacts at the top, to minimize the wires etc...
 
Thanks for your help.