How do you swap out memory?

I currently have GB [2 GB X4] DDR3-1600 Memory Module with 16 GB [4 GB X4] DDR3-1600 Memory Module. I’ve got a motherboard that can handle it. Do i just open my case and take out the memory sticks and put the new ones in? Or do i have to do anything else. And how would you put the new memory in?