How to clean Macbook Pro keyboard without accidentally turning it on

Hello,

can anyone please advise me on how can I clean the keyboard of my Macbook Pro? As I understand it, there is no way to disable the feature, that the MacBook is turned on by pressing any key. (I usually tend to wipe the computer when it is turned of, but this isn't an option, because it immediately turns on. But there also isn't any built-in function to disable the keyboard on a running computer. How am I supposed to clean the keyboard without accidentally pressing on all keys?

I know there are third-party apps that allow you to temporarily disable the keyboard, but the free ones available in the app store in my location seem to be trash. There must be a better way as this is something everyone is dealing with.

Thank you very much in advance,

Barbora