Using 6 core alarm cable from panel to PIR, you connect the alarm pair in the PIR to a spare zone in the panel, removing the link that will be shorting those terminals out. The tamper pair will go in series with the other zones on the global tamper inside the panel. The power pair will pickup from the 12v +/- inside the panel.
Colour choice is yours to be honest, there is no standard, and all alarm co's use different color schemes - best to stick to whats been done at yours though to be consistent.
Remove mains power from panel to be safe inside the panel when working, but leave battery connected. No need to power down. The alarm will sound when removing the panels cover, unless you enter engineer mode on the keypad (but doubt you know the engineers code?)
Once wired, you would need to configure the zone. You more than likely want it as default, so you may find it is already configured for your needs. If so, you wont need to access the engineer menu to change anything.