i'm thinking of amplifying all my seperates speakers w/ a 4 channel amp? how do you wire the speakers seperately?

If you are wiring your high's then wire your left side speakers the channel 1 and 2 channels. Then then the right use 3 and 4 channels. If you have three sets of preouts on your deck I would use seperate amps for my front and rear speakers. This way you can adjust the sound better.

It depends what kind of speakers you have. Because if you don't have component speakers you would not wire them as stated above.