I think the simplest, yet most idiomatic way to say that in English would be this: Cover her eyes with your hands.
Or, as was suggested by brichins down below, the sentence can be made even shorter: Cover her eyes.
if it's implied that it is your hands that you're going to use to cover her eyes.
ell.stackexchange.com/users/6450/Michael Rybkin
"Put your hands over her eyes" would be most natural to me.
("Over" seems more natural than "on" but I can't really explain why.
Perhaps "on" feels like you're saying to touch her eyes, which would be painful.)
If you said "blindfold her with your hand(s)", that would be understood perfectly.
"
Catch her eyes off" makes no sense to me and I wouldn't be able to guess what you meant.
ell.stackexchange.com/users/4468/David Richerby
None of your examples feel natural to me.
As an American in the western U.S., we would simply say "close your eyes," it being implicit that the eyes may need to be covered (by one's hands or something else) to ensure the necessary blindness or surprise.
It is a common enough concept in my area that a surprise should be met with covered eyes that I don't hear people say anything more explicit.
If the situation requires the eyes to be covered by hands (whether it be a playful moment with a child or an intimate moment with a lover), I'd use "cover your eyes."
If asking a third person to cover the second person's eyes, it would be most natural to say, "please cover her eyes."
Again, the use of hands being implicit.
It would be tedious to say "cover her eyes with your hands" as it suggests there are multiple ways to cover the eyes and the most appropriate is with your hands.
This would be highly circumstantial.
Ignoring situations with sexual overtones, I could see using it at a child's birthday party where a blindfold was used by children striking a piñata — until one with a runny nose took a turn, afterwhich the blindfold couldn't be used.
You might then ask a second child to "cover her eyes with your hands" to take the place of the blindfold.
ell.stackexchange.com/users/56469/JBH
As an American (who has lived in the midwest and east coast), a common phrase I would use is Shield her eyes! to indicate covering their eyes so they cannot see.
This has the same meaning as "cover", but the use of "shield" adds a sense of urgency or need to avoid danger.
Because it sounds exaggerated, I most often hear this in playful and joking contexts.
(For example, I was very shy and modest when I was younger, and a friend teased me by saying "oh no, shield your eyes!"
when two characters had a PG kissing scene in a movie.)
Note that "shield" can also mean "protect" in a purely functional sense,
as in the case of debris or wind, which does not necessarily imply that the person is unable to see.
The context should make it clear which is meant, but to avoid ambiguity or for a more serious situation, Cover her eyes! is appropriate and to-the-point.
It would seem a little strange to specify "with your hands", since that is already the most likely method of covering someone's eyes.
But if you would like to specify, Put your hands over her eyes.
is a natural way to phrase it, since the use of "put" requires that you explain what you are going to use, rather than tacking on a prepositional phrase to the "cover" sentence.
ell.stackexchange.com/users/39790/user812786
I'm reminded of one of my favorite songs by Weird Al (Everything You Know is Wrong).
In the song you hear the lyrics: "When suddenly a guy behind me in the back seat Popped right up and cupped his hands across my eyes"
It's a variation of the other answers here, but especially the word "cupped" in this case
sounds like the right way to me.
Also, I think where space is at a premium in song lyrics, if there were a shorter way to say this, he likely would have used it.
ell.stackexchange.com/users/30111/Aaron R.
As a Mississippi native, to ask a person to do this to themselves: Hide your eyes!
To ask someone to do it to someone else:
Hide her eyes!
ell.stackexchange.com/users/71118/RedAlertMom
Not appropriate for the particular case in question, but closely related:
There's a little rhyme you say to small children:
Open your mouth And close your eyes, You're going to get A big surprise!
When the child closes its eyes, you pop a sweet into the child's open mouth.
ell.stackexchange.com/users/71103/recoup
I would like to know how do you say this action in common spoken English.  Suppose that someone puts their hand on someone's eyes in order not to let them see.   So, someone is ordering someone else to this action:   A. Put your hand on her eyes.   B. Blindfold her with your hand.   C. Catch her eyes off ...       So what's the way saying it?
What is an idiomatic way to tell someone to put their hands on someone's eyes in order to not let them see?
ell.stackexchange.com
<phrase-request><spoken-english><idiomatic-language>
ell.stackexchange.com/questions/159208
ell.stackexchange.com/users/59037/Shahrooz
"Cover your/her eyes" is the most common suggestion. "Cover her eyes with your hands" would be understood, although "with your hands" is probably unnecessary. "Put your hands over her eyes" or "blindfold her with your hand(s)" would also be understood. However, "Catch her eyes off" would make no sense to most speakers.
"Catch her eyes off" would make no sense to most speakers. "Cover her eyes with your hands" would be understood, although "with your hands" is probably unnecessary. "Put your hands over her eyes" or "blindfold her with your hand(s)" would also be understood.