Once you break the Microsoft seal, we can continue. Start by taking multiple flathead screwdriver bits or 4 spudgers (The most common spudger is a black or yellow nylon stick with a metal hook at one end.) and put them in these 4 latches to hold them open.
After all 4 tabs are held open, pull up on the top half of the case. The bits should pop out(don't lose them!). Lift the case up and make sure the tabs don't reconnect.