I applied online, where I went through a series of general questions (which included references, address, etc.). Then you go onto a questionnaire, that is just common sense. For example, it will say "You are...always on time" and then give you the different options of how you can respond to that answer, there is about 60 questions and it took me a bit longer than 10 minutes.
You then continue onto a more interactive questionnaire, that gives you situations that could happen in store and you have to answer them how you would try and solve them if you were working there.
Once I finished my application, I got an e-mail almost immediately, telling me that I had passed the assessments and for me too choose an interview slot. Once I had chosen an interview slot, they sent me an e-mail explaining what I would need to bring to the interview and where it would be.
On the day of the interview, I was shown into the staff room (or what looked like it) and was sat down, while the other interview was finishing. The staff room was very lovely and lively and the staff seemed to get on together really well. Then a lady took me into a room, where she explained that she was going to be doing a role play and what I had to do. She gave me a pack of resources and left the room for 5 minutes. TIP: Don't think that you'll have extra time, make sure to try and read the information as fast as you can because otherwise you will miss things out. She came back in and was immediately playing the role of the customer. It took us about 5 minutes and it went pretty well. Make sure you smile, keep eye contact and always look and speak happy. After that she gave me a sheet that said: "What went well?", "What didn't go so well?" and "What would you do next time to improve?" after I completed that she went out of the room, and a manager soon followed after.
She talked to me and asked me the pretty obvious interview questions, she was very nice and friendly. I almost forgot it was an interview at one point! They definitely do there best to relax you, and it makes you talk better.
We then discussed hours, and because I'm at college, it got a bit complicated. I passed the interview and the role play. However, they put my application on hold, while they sorted out the hours that were best for me.
Good luck, and relax!