I have 3 children ranging in age from 4, 3, and 1. My husband left the day our youngest daughter turned 2 months old and since I was just starting my pre-reqs for nursing (I just got in!) I had to find a daycare. So I have experience with what I'm doing here.
First, make an appointment to go and see the daycares that you've narrowed it down to. Usually the best time to go is between 12-2pm. Nap Time. Easier for teachers to give you a few minutes to answer any questions you have when they don't have a half a dozen kids asking for attention.
Make a list of questions before you go. Times, prices, prices for being late. Whether or not you're child's age group goes anywhere, does any special projects. What you'd need to supply for the child while they are there. What kinds of policies do they have regarding sick children and pick up times and return times. Discipline methods. Etc.
Talk to the daycare's director, the teacher that would care for your child and everyone else you can get your hands on.
Then make a decision based on what you've been told, what you've read, what you've heard and how you felt. You want to be comfortable around the people taking care of your child. Most importantly you want to make sure you can trust them.