Design 1 
The main idea behind this design is to have a very simple layout with big button, big pictures, and simple flow.
Design 2
This was focused on making the automation process as simple as possible. The idea was to have every item you buy have the option to buy it on a regular basis.
Design 3
For my extreme design, I decided to focus on an illiterate point of view. So I sketched out an interface made with mostly pictures.