Job question

Mariah Lynn • Automotive mechanic, Lost my 2016 christmas baby, due 06/05/2017

Today I had an interview at a job" A" that I wouldn't mind having, might love, might hate. Tomorrow I go in for my 2nd interview. But about an hour ago I got a call from a job "B" that I would like more than job A. I don't have my interview for job B till Tuesday.

Now my question is if job A wants to give me an offer tomorrow, how do I go about holding off on the offer until I visit job B and do that interview? What should I say to job A?

Thanks!