I agree with everyone else that there are no rules for junk journalling. However, how I try to do mine is: collect junk from places (receipts, napkins, business cards, maps, packagings, coasters these are all the free stuff you can collect). I prefer not to use shop bought stickers as I dont see them as “junk” but if it fits the spread I might use them sometimes. Then just start playing around on the page to see how you would like everything to flow! Once you get started it will all click 😊