AN 11YEAROLD (whose name I won’t reveal) accidentally spilled
water on a laptop, and wanted to know how to clean it up before any
parents found out.
Liquid and electricity don’t mix. When the two meet, the liquid can
destroy a great deal of electronic circuits. It can also send you a
serious shock if you’re not careful.
I’m going to assume here that you’re not reading this on the wet PC.

Best not to use it until everything has dried up.
Immediately after the spill, make sure your hands, and the laptop’s
power button, are dry. Use a towel if necessary.
Turn off the computer…and I don’t mean shutting down Windows
properly. Press and hold the power button. The computer will shut
down completely after five seconds.
Next, remove any source of electricity. Unplug the AC adapter from
the wall socket. Then remove the battery, if the battery is removable.
You’re now safe from shock. Unplug anything else that’s plugged
in—mouse, cables, flash drives, and so on. Open and remove anything
that can be opened and removed with relative ease. For instance,
remove the RAM and the hard drive or SSD.
If the liquid was something that dries sticky, such as alcohol or
sugared drinks, send it to a professional for a thorough cleaning.
But if you just spilled water, you have a chance of drying it out
yourself.
First, dry the outside thoroughly with a towel. Then clear off a table
and put a fresh towel over it. Open the laptop as wide as you can, so
that the screen and keyboard are on the same plane. Then put it, face
and keyboard down, on that towel-covered table. Leave it there for at
least a couple of hours so that the water can drip out.
Then put it all back together and see if it works. If it doesn’t, take it
to a professional.
By the way, I gave entirely different advice to the young reader who
asked the question. I recommended confessing and apologizing for
the mishap.