Before upgrading your computer's RAM, be sure to find out what kind you need.  Look for speed, size, type, Cas latency, timing, and pins.  Make sure everything is compatable with your motherboard.  Once you know what you need, look around for good deals.  Try Ebay, tigerdirect.com, or newegg.com for the best deals.  Once you have your RAM, follow these steps:

1. Handle RAM only by the sides.  Do not touch the chips or the gold connectors.  Store in a dry, antistatic location (i.e.- antistatic bag).

2. Open your computer case.  Touch an unpainted metal part on the inside to ground yourself or attach an antistatic wrist strap to a metal part of the case.  This will ensure proper grounding and prevent electrostatic damage.

3. Locate the RAM.  Once you've found it, press down on both clips to unlock the stick.  Carefully lift the RAM straight out by the sides.  Place on an antistatic bag for most protection.

4. Lign the new stick carefully inside the open memory bank.  Press down evenly on both sides of the top.  One side will *Click* into place.  When this happens, press the otherside until that also *Clicks* into place.  Ensure the RAM is completely seated.

5. Repeat for other sticks if neccessary.  Close the case and plug everything back in.  Check the BIOS settings to make sure the RAM is recognized.  If it isn't, reseat the RAM following the above directions.  If it still doesn't work, make sure there is no dust on the gold connectors or inside the memory bank.  Also check for black spots as this is a sign of electric damage.

Good luck!  And remember to check for compatability.