A lot of this is common sense, but just to re-affirm it! I recently left my job at ASDA so feel able to divulge this information. I was in charge of recruitment in one of their stores, and screened application forms, ran group selection interviews, before feeding back to all the other department managers about who I would recommend.
THE APPLICATION FORM
-Application forms are a game. As long as it doesn't stick out like a sore thumb, say what you think they want to see.
-Exaggerate things. For example, in my store, I was once in charge of a two man team in my store for scanning the offsales three times a week i.e. all products where the shelf was empty. On an application form, I would make it seem more important: "team leader on an internal availability process". If they asked me about it, I would say that I led a team, and I improved availability by paying attention to detail, and working with my colleagues to improve their performance. A bit of an exaggeration, but all technically true. It is all about how you word things.
-Shops will love you if you somehow manage to include words such as 'cost effectiveness', 'profit' and 'exceeding customer expectations'.
-Fill out all parts of a form. May sound silly, but some people skip sections because they think, as a Shop Assistant, it doesn't matter too much and 'everyone gets a job'. Well, they don't. As a former department manager myself, your neck is on the line everytime you recruit someone, even evening part time staff. If they don't work as hard as they can, the day staff will get annoyed as they have more than their share to do. Morale drops, so day time productivity drops, and the department is on a slippery slope. So you must give the impression that you are a hard worker, that you have a lot of common sense, can be trusted, and that you care about doing a good job. Otherwise they won't trust you.
THE JOB INTERVIEW
-At ASDA it is in the form of a group selection, with between 6-12 people also being interviewed. One employee will run the session, and there will be observers in the background assessing.
-If run properly, there will be three group tasks. When I ran them, it used to be:
a) speak to your partner, find out as much about them as possible and report back to the group.
Here, we are looking for you to communicate well with your partner. Be confident, encourage them. When you report back, we like you to be enthusiastic. Nothing ground breaking. Generally, just being a nice person who is confident without being completely dominating in these interviews is more than enough.
b) In a group of four, design a Christmas uniform.
This is just to see how well you work in a group. Make sure you contribute equally to discussions and don't get left out by louder people. If you notice someone is quiet and you have said your piece, try and bring them into the discussions. "what do you think dave?". No one cares how good the final product is: just play a part and work as a team. Again, be a nice person!
c) In groups of five, using a pack of cards, build a house, and then report back to the group on why they should buy your house.
The person running the session may give you an object halfway through to put into the house, to throw you. Basically, again, teamwork. Don't be too dominating, but try to take a lead, involve everyone, and don't be shy. Just showing basic things like taking an interest in others views will get you everywhere. When reporting back, do so with a smile, and a bit of personality.
For all the tasks, you will be assessed by people on a basis of 1 to 4, with 4 being good. Generally, a mixture of 2/3s will get you employed.
Don't worry about these, and don't be thinking "oooh I haven't shown this!" Just be yourself, be a nice person who can work in a team, and be confident. That's all you need to do! And be polite.
Contrary to popular opinion, supermarkets and shops do turn people down. We recently turned a lot of people down for being rude. One group would be reporting back on a task, and the others would be sitting their chatting amongst themselves. We rejected them, because what if we're in a team meeting and they're ignoring what is going on? The message won't get across.
With shop interviews, for general assistant work, they're not looking for technical knowledge, or anything advanced. Just that you're a nice person, that you can work in a team, and that you're willing to work hard and learn. That's all.
And I am sure that applies to most shops, not just ASDA. That was my own experience, hope it helps.