How to protect a keyboard from a cat?

"Use a Kitty Keyboard Cover.

The Kitty Keyboard Cover, or as we like to call it, ""Kitty Keyboard Kover"", is a simple and elegant solution to your cat(s) walking all over your computer keyboard.
Made from very strong 1/4"" acrylic (plexiglas), the cover easily supports a 16 lb (quite large) cat.
It also, to a certain extent, helps keep all the kitty hair and dust and dirt out of the keyboard. There's plenty of room for a deeper keyboard, even the ones with the built-in touchpads and media buttons."

"I think the best way to do this is to teach him it's not good to stay on your keyboard.

With a child you would say ""You can't do this"" and he would understand. But animals doesn't understand portuguese english (I'm Brazilian XD), so that tatic of sprinkling some water on it is good.
Everytime he manages to do this, sprinkle water and take him out. Your cat will get upset and after some tries he will link the bad idea of ""water in my face"" with ""keyboard"", and that going on it is a bad idea; they won't try to do this anymore.

You can do this also with direct flashing light (2 flashes at most, please) and some simple words, like ""No you can't"". The words will get linked too, and after sometime you can try only to say ""No you can't"", and they will obbey.

I don't think that giving food or toys will help. They don't want food or toys, they want to sleep on that confortable thing that your keyboard is. And you need to tell them they shouldn't.
Of course that if you aren't giving them enough attention or food, they want food and attention, so you should be right it's not the problem, first of all.

After that... good luck =D"
"I think the best way to do this is to teach him it's not good to stay on your keyboard.

With a child you would say ""You can't do this"" and he would understand. But animals doesn't understand portuguese english (I'm Brazilian XD), so that tatic of sprinkling some water on it is good.
Everytime he manages to do this, sprinkle water and take him out. Your cat will get upset and after some tries he will link the bad idea of ""water in my face"" with ""keyboard"", and that going on it is a bad idea; they won't try to do this anymore.

You can do this also with direct flashing light (2 flashes at most, please) and some simple words, like ""No you can't"". The words will get linked too, and after sometime you can try only to say ""No you can't"", and they will obbey.

I don't think that giving food or toys will help. They don't want food or toys, they want to sleep on that confortable thing that your keyboard is. And you need to tell them they shouldn't.
Of course that if you aren't giving them enough attention or food, they want food and attention, so you should be right it's not the problem, first of all.

After that... good luck =D"

"I can't believe nobody suggested this yet.

Put two cardboard boxes on your table. Boxes are like magnets for cats. They'll jump in the box and leave your keyboard alone."

Cats don’t like the smell of oranges (or other citrus fruits), so you could try cleaning your keyboard or the desk with one of those orange-oil based cleaning products.