wiring a Relay board with a separate power supply.

I need some assistance on figuring out how to wire a specific relay board (5v version of http://www.aliexpress.com/item/Free-shipping-8-Channel-5V-Relay-Module-12V-Relay-Module-Interface-Board-for-PIC-AVR-MCU/560377256.html?tracelog=back_to_detail_a) with a separate power supply. I have been googling this for a little while and I am finding instructions for other relay boards, but not this one.

Any guidance would be appreciated.

There is a 5V line on that board, connect that to the +5V on your external power supply. Connect the other lead on your power supply to the ground of the arduino. You might find a ground on the relay board, connect that to the arduino ground as well.
The outputs from the arduino then connect the control signals to ground to turn the relay on.

Can you provide a list of what it says on the connectors the photos on that page are too mall to see.

I am working from memory (and the picture), I'm pretty sure the pins are (in order) Vcc, Ground, Int1-8, COM, and another Ground. The last two pins have a jumper on them. If i connect the ground to the arduino, how can I be sure that the relays are grounding to the power supply? I will have 4 relay boards attached to this arduino so if the relays do not ground properly I will blow the arduino.

If i connect the ground to the arduino, how can I be sure that the relays are grounding to the power supply?

Because as I said you also connect your external power supplie's ground (-ve ) to the arduino ground. Connect the +5V of your external supply to Vcc.