When ever I take my laptop outside to work, I suddenly realize just how dirty it really is. The dust and spots on the screen really show up when the sunlight hits them just right. For this reason, I would recommend taking your laptop outside when you clean it, in order to do a thorough job.
First of all make sure you turn the laptop off prior to cleaning. For cleaning the screen, LCD screen cleaners work best and can be bought at your local office supply store. Lint-free dust cloths are great too!
For cleaning your keyboard, the best thing I have found is the tiny portable keyboard vacuums. A little isopropyl alcohol and a damp sponge will do a nice job of sanitizing the keys as well, just be careful not to let any drip down into the laptop, and don't get any on the LCD screen.
Use these tips and your laptop won't need another cleaning for about a month.
