Why isn't there a separate sign for the word 'do'?
ASL has its own distinct grammar and doesn't use English auxiliary verbs like 'do,' 'is,' or 'are' to form questions. Instead, ASL uses non-manual markers, like raising your eyebrows, to turn a statement into a question.
Do I sign 'you' at the beginning or the end of the question?
You can sign 'you' at the beginning, the end, or both! Placing 'you' at the end of the sentence while holding your questioning facial expression is a very common and natural way to make it clear you are asking them a question.
What if I use furrowed eyebrows instead of raised eyebrows?
Furrowed eyebrows are used for 'Wh-' questions (who, what, where, when, why). Since 'do you' initiates a yes/no question, you must use raised eyebrows. Furrowing them will confuse the person you are signing with, as they will expect a 'Wh-' question.