Creating a customer journey map from persona

I was asked to create personas and customer journey map using analytical data and other online data (Without talking to the actual customers).

So, I created a few buyer personas based on some data (Google analytics, Forums, Social media feedback). Now, the next step is to map that into the Customer Journey, but I am lacking the technical and practical knowledge regarding this step. Is there anyone has done this before, from buyer personas to the customer journey?

The requirement is to redesign the website, and it is a retail website.