Why do I need to furrow my eyebrows?
In ASL, facial expressions provide important grammatical information. Furrowed eyebrows are the specific non-manual marker used for 'WH-questions' (who, what, where, when, why, how). It signals to the other person that you are asking them an open-ended question.
Can I just point back at the person to ask 'how about you'?
Yes! In casual, fast-paced conversations, simply pointing back at the person while furrowing your eyebrows is a common way to bounce a question back. However, the two-part sign shown here is very clear and great for beginners to practice.
Do I have to use both hands for the second part of the sign?
While you might see some signers use a one-handed 'what' gesture casually, using both hands with palms facing up is the standard and most clear way to sign this specific phrase.