I know a few young people who pick up some extra shifts in bars or at music festivals for some extra cash, mostly young people wanting to pay off student loans or save a deposit for a home asap. I also know that many employers aren't too happy about it and try to ban their employees from doing it, because they're afraid that their staff will be really tired at work. But as long as your employment contract doesn't ban you from taking on a second job, I don't think it's a bad idea at all. I have my own business as a side hustle and that means a lot of the hours I put into my business are unpaid. I hope this will pay off in the long run, but it's a time and energy consuming way to make some extra money. If you really just want to make a bit of extra cash, picking up a few shifts in a second job is probably the easiest way to do it. I know someone who works one or two evening or night shifts a week in a food factory. Because they get paid extra for shift work, they actually make a decent amount of money per hour + good benefits.