Well here’s a question I just had to answering straight away:
Question: you dont like the chick….total seahag…and theres no chemistry.
What would u do after….
Wait 3 days to chat with her?
Try to chat with her on a saturday night?
If u dissappear and she emails…would u text and apologise for been quiet?
Wish her good morning the next day?
then tell her that work was so crazy u cant balance your work and social life?
Would u do that? do
Answer: I would just move on. Why try if nothing worked out. Is their more to this story?

to answer your 1st Q..put a brown paper bag on her head
HUH?
Don’t lie to her. Just tell her there was no spark. It’s much quicker and more painless than leading her on to thinking you like her.
I would text her the next morning saying "Good morning. Did you like the date from yesterday?" Then whatever she says I would let her know that I didn’t really like it and that we shouldnt really go out again. One way or another. It’s probably going to be nicer though.