Find out from your RAM manufacturer exactly what RAM will work with this machine.  For me, Kingston says their KAC-MEMHS/2G is the stuff.

First things first.   Power down and take the battery out.  Taking the battery out releases the tabs on the keyboard that you’ll need to push out of the way next.

The keyboard is hinged at the bottom, and there are 7 tabs that hold the top of the keyboard in the frame.  The ones on the left by the Escape and Tab keys are fixed, but the ones on the right, by the F4, F8, F12 and Del keys need to be pushed in to release the keyboard.  You can use something thin like a credit card to hold it out of the frame as you work your way from right to left.  Once you have the tabs released, the keyboard will need a bit of flexing to get past the fixed tabs.

It makes things easier if you disconnect the keyboard. Slide the white bar of the ribbon lock down and it’ll release the keyboard’s ribbon cable.

I like what they did inside here.  There are four screws labeled (1) DOOR that you need to remove.  Next, a diagram shows how to use a screwdriver to push out the bottom door through the hole marked (2).  After this, you can close the lid and lay it upside down.

There’s the RAM… gently push the two metal tabs that lock it in place, and the RAM should pop up.  Gently pull it out and insert the new RAM, observing the notch in the contacts.  Push the RAM down level until both the metal tabs click into place.

Reassemble.

Snap the bottom panel back onto the main body.  Check that the seam where they meet is even and flush.  Reverse the disassembly process from here.