How to take apart MS Optical Mouse Blue

[Sandpiper]

I have an out-of-warranty MS optical mouse blue, with a sticky right button,
which I'd like to try to fix myself. However, it is not obvious to me how
to open up this mouse. Can anyone tell me how to approach this? Thanks.

 

[~misfit~]

I have an out-of-warranty MS optical mouse blue, with a sticky right
button, which I'd like to try to fix myself. However, it is not
obvious to me how to open up this mouse. Can anyone tell me how to
approach this? Thanks.

There's a phillips-head screw under the big sticker.