This step is for the bottom side of the laptop (where HDD and memory are). Using an opening pick, to not damage the case.

Starting in an edge, pull the pick in. Slide left-right/right-left, to create an opening.

No problem when you hear a click-sound.

When there is an opening, use a spudger to seperate the rest of the downside of the case. Slide it trough the whole downside.

Slide further with the spudger to the side where are the least ports (one USB port). Optionally use a opening pick, if necessary.