Next, flip your laptop upside down and remove the 2 sets of screws highlighted in yellow with your Phillips 0 screwdriver, There are 2 sets of 2.
Then open the laptop to roughly 45 degrees and place it on its side as shown. From this position you can wiggle the dust cover off.
If you are having trouble then open or close the lid a little further. When you have it in the right position it will require no force, it will slide right off.