Step 1 - Disconnect the power cord and remove the laptop battery.

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Step 2 - Open the laptop, and look at the "hinge cover", which is the area above the keyboard and below the screen. You should be able to find an area with a small indent that would fit a small flat-head or other prying tool. If you do, pry gently with an upward motion to remove the hinge cover, then proceed to step 4. If you do not see an indent, proceed to step 3.
Step 3 - It could be that your laptop is designed with a screwed-on hinge cover. Most that are like this have a long battery located in the "back" of the laptop. Since it is removed, you should be able to see if there are any screws in this area. If not, look for any other screw on the bottom of the laptop that is in a position to be holding on the hinge cover. If you find none, then the hinge cover can probably be pried off just as easily, but without the convenience of a "starting point".
Step 4 - Unscrew the keyboard. Most laptops have anywhere from 2-5 small screws in the top of the keyboard. Make sure you put these together in a place where you won't knock them onto the floor or carpet (voice of experience speaking here - a bowl or saucer from the kitchen, really anything to keep them from rolling off will do).
Step 5 - Slide the keyboard "back" then gently lift it up and out. It will be connected with a cable attached either with a standard plug or a different connector. As a rule of thumb, don't force anything. This image shows one of the types of connectors you will probably encounter. Once disconnected, take the keyboard out and set it aside.
Step 6 - At this point the memory DIMMs should be visible. If not, then you have one of those horrible laptops with memory tucked in the deep dark regions and we will not be covering how to replace it in this article.
Step 7 - There are two little "arms" holding the memory sticks in. Pull them gently to the sides to release the DIMM(s), which will then tilt upward. Remove the DIMM(s) at the angle they default to, and install new DIMM(s) at the exact same angle. Once the new memory is firmly inside the slot, press down on the DIMM to rotate it back into position to be held by the "arms". This image should help with this step.
Step 8 - Put everything back in reverse order of how you removed it, and it will work perfectly!
Enjoy your new memory!