Based on the data you got from previous research, try to "create" a first version of persona. It's as simple as possible by now, just to map our current hypothesis about who have the problem we are solving. Do not invent information about users, try to mix the data you have in a logical way like finding quantitative and behavior patterns. For example "We've discovered that people who give up of our checkout process are proportionaly from a specific region" so, I will define that this protopersona will come from there.

Remember that it's just a first hypothesis! You can create as many as you want.