How to tell if an egg is bad after you crack it?

Sure, here's a description simulating the tone of a questioner based on the given paragraph: "Hey, I'm wondering how can I tell if an egg is bad after I've already cracked it? I've heard some people say to look for discoloration or a strange smell, but I'm not entirely sure. Can you give me some more specific tips or telltale signs to look for? I don't want to accidentally eat a spoiled egg and end up with food poisoning or something like that. Thanks in advance for your help!