CHILD: "Full-Time Kid" with Mya.

[laughs] [music playing] (EVIL GENIUS VOICE) Welcome to my full-time lair.

My name is Mya, and this is my cat, Meowa.

And today, we're going to teach you how to make invisible ink to hide all of your secrets.

Mwua-ha-ha-ha-ha.

Let's get started.

Here's what you'll need-- a spoon, some paper, some cotton swabs, a bowl, half a lemon, some water, and a lamp.

The first you'll want to do is get your lemon and squeeze all the juice into the bowl.

You can ask an adult's help for this one.

Once you get all the juice into the bowl, you're going to pour in a few drops of water.

Now stir.

[stirring] Dip a cotton swab into the mixture and write your message onto the paper.

When you're finished, let it sit for about three to five minutes.

Once you've let the lemon juice on the paper sit for three to five minutes, it should be completely invisible, like this.

To decode your message, all we have to do is put it under a light bulb for 5 to 10 minutes or until it turns brown.

Make sure to be patient.

This might take a while.

[music playing] I'm not very patient, so-- [music playing] [sighs] Any day now.

When you've held the messages over the bulb long enough, it should look like these.

This is the three I made-- full-time spy, hello, and subscribe.

That's it-- or is it?

(WHISPERING) Please subscribe.

[music playing] MAN: You wanna give me a line about, uh-- [laughs] [beep] [mouth sounds] [beep] [laughs] CHILD: "Full-Time Kid" with Mya.

[laughs]