Need best solution to allow client to manage blog

I have created a Wix website. I am happy with the result so far. I want to add a blog page, that can be managed by the person I created the site for. The goal is to allow them to add/edit blog posts. I do not want them to be able to break the page template or have access to other pages and elements on the site.
Does anyone have a suggestion or solution on how I can accomplish this?

See original post by edlee