Q: Can I get you anything? (clerk)

1. I'm not ready yet.
2.
3.

(Is the answer 1 correct? What other answers can we say?)

2 answers

1 is correct, yes.

Also ...

"I'm just browsing, thanks."
or
"Just looking, thank you."
or
"I'm just waiting for them [gesture at others who are with you], thanks."
or
"Yes, do you have this in a size 8?"
or
"Yes, do you have this in red?"

You can make many more up.
2. No thanks, I'm just looking.
3. Yes, please. I'd like . . .