Hey Eddie
Welcome to the forum
ManualIf you brought your self a pair of pro-jumps there should be a manual in the box, if there isn't please email dan@ukgooddeals.com with your name, address and order number & request one and he will get one posted out to you.
StrapsYou've more or less figured out how to strap your self in - just make sure that the straps are on the out side so you don't get them caught with each other.
If the straps are not tight enough you can adjust this by using the second hole on the foot straps (see picture below)
Knee BarThe knee bar problem is a common one and theres a few ways to rectify this:
1. Use some knee pads (the pit dirt ones are ideal for this)
2. Use additional foam and tape to pad the area out more (picture below for how Carl did his)
3. Use the straps to get a secure fit
Other things you may want to do1) Taping your springs - this will protect your springs from scuffs, marks and dents! See Steve's springs below: Just wrapping a few layers of duck of hockey tape will do the trick. some people have also popped over a bike inner tube cover first
2) Protecting your rubber feet - Make tyre socks - read the following threads for more details:
Make your own socks thread -
http://www.projumpforum.co.uk/index.php?topic=789.0Jasons tyre socks for sale -
http://www.projumpforum.co.uk/index.php?topic=1002.0Hope this helps and happy jumping