How to setup?

I am new to setting up sound system.
Just started buying stuff for my sound system
These are the units I have. Would somewhat like to use it all if posible.
*15 band equalizer dual channel
*active crossover 2 channel
*(2) 12" powered 2-way speaker
*(2) subwoofer with amplifier
*(2) 15" 2-way speaker with amplifier

What else do I need?