How do you activate a cricket phone with a Verizon sim card free?

Call 1800 Cricket (1-800 274-2538), and give them the ESN number, which is underneath the phone's battery next to it's serial number. Perhaps you should write it out before hand so it'll be easier to read when prompted.

They will give you a MDN number and a MIN number, and a CDMA number. Write these down.

Then, read your booklet that came with the phone (that has these directions with it) for how to access the programming menu, and enter these three sets of numbers to activate your phone.