Mom: The sign for "mom" is made by forming a "C" shape with your dominant hand and touching your chin.
Know: The sign for "know" is made by touching your forehead with your dominant hand, then bringing your hand down to your chest.
How to sign: The sign for "how to sign" is made by making the "S" sign with your dominant hand and then moving it back and forth in front of your chest, like you're signing.
Putting it all together:
1. Sign "mom."
2. Sign "know."
3. Sign "how to sign."
You can also add a facial expression of understanding or inquiry to make your meaning clearer.
It's important to remember that sign language can vary depending on the language you are using (American Sign Language, British Sign Language, etc.) and the individual signer's style. It's best to find a qualified sign language instructor or use resources specifically for the language you're learning to ensure accuracy.