Here's what people have said about working and interviewing at B&Q.
It has changed a lot since I started, so I don't know. I believe there is some sort of questions & tests to get through, because some people are let go at an early stage having failed whatever they were given. Everyone who is taken on has to complete stuff on the computer for Health & Safety, & 2 other things. It's a pain, but a requirement that has to be done once a year. You are also required to wear reinforced toe cap safety footwear for your own protection. Shoes are supplied by B&Q.
Not much prep to be done, computer literate and a general wanting to help people will pretty much get you through.