Answer:
The same way you change any halogen head lights. Remove the retaining ring, turn the socket, pull the bulb out, remove the wiring, connect wiring to new bulb, put bulb in headlight, and reattach retaining ring. DO NOT TOUCH THE BULB WITH BARE HANDS UNDER ANY CIRCUMSTANCES!
A message to ID2903905872:
Please do not be so rude to people on here. If you have nothing constructive to say, then don't say anything at all. To refute your answer, I'm pretty sure the OP wasn't asking about replacing the headlights, instead installing separate spotlights.
Answer:
The instructions for these are very vehicle and light unit specific and you should ask someone who you trust locally to help you with it.