If you hold it so that the TI logo is face up and readable, in the lower right corner of it, there's a notch between the two parts. Take off the end cap and open up the case with this notch using a flat-head screwdriver. It's a sturdy case, it'll be fine. At least, that's how I open mine.
Two places NOT to try to open it are the circular hole and the square hole near the bottom of the case. There are capacitors there, and if you accidentally bump one of them off, the programmer part of the device becomes useless.