How do I realign the case to fit snugly again?

Dropped tablet onto tile floor from approx. 2 ft high, hit on corner of device. Case popped open slightly along the left side, and am unable to close it snugly again. Device works fine but this thin gap along the edge may allow dust and dirt inside.

Have checked several repair videos which show how to open case completely but simply end with the instruction, "Reassemble device by reversing these steps." But no clear example is given of HOW to realign the case so it snaps back into place properly, what tools may help.