You are going to want to prepare your computer to install the RAM.
You will want to first turn off your computer.
Unplug the power cord.
Then turn off the switch for your Power Supply Unit (PSU).
Now wait 10 seconds to make sure your motherboard is fully discharged.
Now that your computer has been totally stripped of power, open up the side of your computer case and examine where your motherboard and the RAM is located.
Now that you have located where your RAM is, take note of how many sticks are in there and how many empty slots there are.
Remove the RAM in there if you are crossing companies/kinds of RAM but if they're the exact same and there's space, might aswell leave them in.
Now that everything is prepared and ready, it is time to install the RAM.
It's as easy as grabbing the RAM stick and slotting it smoothly into the slot (make sure the right way in) it should just click nicely into it.