how do i remove the drip tray from my fridge?

there is a small drip tray at the top of my fridge on the back wall just below the freezer. water is running down the back wall of teh fridge and pooling at the bottom. It looks like water drips into the small tray and i assume down a hole in the wall of the fridge to be evaporated. I also assume the hole is blocked. I need to know how to remove this tray to unblock the hole