There's a few rules you should follow if you want to join, but don't fret! There's not many and they're very fair.
1. You have to have a webpage of some kind on which you can put the code. There's not much point otherwise!
2. Your aroma should be exactly that -- an aroma. Something you can physically smell. It doesn't necessarily have to be edible (we can all agree old books have a heavenly scent, but I wouldn't recommend eating one...), but it needs to be olfactory. Nothing abstract like "sparkles" or "purple" or the name of your favourite character. (Your favourite character's perfume, yes. Themselves, no!)
3. Please put the code up before you join. If the code isn't on your page when you join, you won't be listed.
4. You may display the code on any site you own, but only five will be displayed with your name on the members page. You do not have to submit multiple requests for multiple sites; simply add your other URLs in the comments section of the join form. Remember to have the code up on those pages, too! (^^)
5. Yes, you can have the same aroma as someone else, as this is not a first-come first-served clique, and your aroma will change with your next layout!
6. No troll/hate sites will be allowed to join, period. I can't believe we still have to say this in 2021, but hey. The internet might change, human nature never will.