Does this make you a little nervous? Don't worry! There are several options for you to do it right:

Option 1: For pictures that are copyrighted, has a © on them, does not have a CC-licence or you are just unsure: reach out and ASK the creator! If it's okey with them, you are good to go. Next to the reference below the picture, write "used with permission of the copyright holder".

Option 2: Search for open source pictures!

Option 3: Make a picture yourself. Yes, you can use AI and credit OpenAI, Microsoft or the kind of AI you use (and make sure to check the user agreement it's okay to use - check the fine print!).

ALWAYS credit the creator! Even if it's public domain, if someone made it the least you can do is credit them :)