You can apply online or ask for an application form in your local co-op store, fill it out, return it and wait for them to contact you. You may be called in for an interview in store. If so all it will be is a few basic "why do you think you'd be good for this role" questions and some basic questions about your availability. Then you are given a form and 20 minutes to fill it out, just with some basic questions about customer service (I assume this is to see wether your written communication and persuasion skills are good) then I was told on the day that I got the job.

It was nice and smooth and very intuitive. I liked how I had help from the website to prepare for the interview and so I was able to fully explain my previous experience.