Before you do anything, make sure you know where each key goes on the keyboard. You might want to make a rough sketch just in case you are as sad as me to do so.
Use a small flat heat screwdriver to lever each key off the board. Each one should simply pop off. If you have trouble you'd may as well leave them. The keys may have small pads underneath. Make sure you keep the pads with the corresponding keys.
Clean the keyboard with cotton buds slightly damp with water. If they are too wet, water will drop into the keyboard and may cause an eleectrical fault. Repeat this procedure again using rubbing alcohol and cotton buds but not the foam rubber as it disintegrates when used with alcohol.
Some keys may have wires attached and some grease on them, clean these first with cotton buds and naptha if you have it. Remove all traces of the grease.
Place all keys in a kitchen strainer. Spray with household cleaner and let stand for 5 minutes. Rinse with hot water and place keys on paper towels to dry. Let them dry completely.
Place all the rubber pads in a kitchen strainer. Spray with household cleaner and let stand for 5 minutes. Use stopper in the sink so that you don't lose these if they jump out of the strainer. Rinse these thoroughly with hot water and place on paper towels. Fold the towels over and press to squeeze most of the water out of the pieces. Again, let them dry completely.
Place all the rubber components into the keyboard. Install keys with wires. Make sure wire is secured in the key, usually snapped into place. Place ends of wire in the guide slots adjacent to the key location as you align the key. Firmly press down to snap the key into place. Install the rest of the keys by aligning and firmly pressing down.
Hope this makes your laptop all squeeky clean. You might even get some stale biscuit crumbs as a reward. Mmmmmmmm . . . stale biscuit crumbs . . . . .
Good luck
mwp
Hello. I'm Mr Pweg.
