I want to program media player shortcuts on my keyboard...How?

I have a logitech k320/500 keyboard...the website said it came with media short cuts, just not the ones I really need - switch tracks.



How do I reassign the premade short cuts to preform the actions I desire?



I have already been to the logitech website and dl their software to change buttons, but they are just preprogrammed features, (I can however program one of the keys to open media player, just not change the songs)



I will install any software needed, or copy ur script and with guidance, install that...