how do I put up my nets on upvc windows?

I have just had double glazing fitted and I need to put my nets back up.
Down stairs the vents are right at the top of the window, I have been told I need to use net poles but if I put them below the vents they look odd as I have a gap.
Upstairs I have a gap above the vent where the poles will fit but how do I attached these to the window. I did buy the sticky net rod supports but they just fell down, please can you advise.