Don't Say "Let Me Know If You Need Anything" if You Actually Want to Help Someone
Bad things happen to our friends and family and we want to help, but we don't necessarily know how we can and say "let me know if you need anything" to fill the void. Redditor usapeaches argues this isn't the right thing to say because you're actually burdening someone with the need to reach out to you for help. When someone needs your assistance and you want to offer it, be specific.
When your friend loses a loved one, your sister ends up in the hospital, or something generally bad happens, you want to assist. It's important to be specific in these instances because people who are in a place where they can't handle their normal day-to-day life on their own aren't going to have an easy time asking you to do them a favor. Offer to watch their kids, pick up groceries, cook them food, or walk their dogs. Think about what you can do to help them, rather than task them with assigning you—and everyone else—who offered. While there's nothing inherently wrong with letting someone know you're there to help, if you really want to make yourself useful then be sure to offer specifics. When you need their help someday, they'll remember.