I want to get my make-up done

[LadyClariceCannockMonty]

in a department store for a night out. How do you do it? I'm assuming you can't just walk in and say 'I'd like you to do my make-up for free.' Do you have to book? How do you ask? Are you obliged to buy products? TIA!

For a night out I would go to a counter like Urban Decay or benefit. I book in advance and usually buy a product or two. You are not obliged to buy but it seems only good manners to do so.