A closer look
The sticker gives you the required info in case your motherboard BIOS allows you to change the timings. The IBM Lenovo X60s BIOS does not need this, it takes the info from the SPD chip of the memory module.
G.SKILL uses BGA chips with their own logo on it. I would think they buy blank chips from one of the big manufacturers and print their logo on it.
Installation
The installation procedure depends on the notebook but is generally really easy. All you have to do is remove a couple of screws. Before doing so please check if you lose your warranty by changing memory on your own.
Remove two screws on the bottom to get to the memory module slots. Don't forget to shut down your system. If you go to hibernation mode and boot after the installation Windows startup will crash because it does not expect a different memory size. When it does Windows will prompt you on the next reboot if you want to do a regular startup, everything will work fine then. But you might lose some data. Also removing the battery is a good precaution in case there is still some voltage going around the memory modules when the notebook is powered off.
Take out the stock 1x 512 MB stick. In order to remove the module, you gently press two metal clips to the outside and the memory comes out easily.
Now put in the two shiny new G.SKILL memory modules and screw back the lid.
After power up the BIOS shows you that everything went well with the installation and your system now has 1 GB of memory installed.
On the left you have the CPU-Z readout with the stock memory, note the 333 MHz but at rather slow timings. On the right is the new G.SKILL memory, it's running slower at 266 MHz but comes with better timings of 4-4-4-12.