You have to complete all the "Badge Bits" for the Badge you want. Badge Bits are tasks that (1) Create a tangible product, (2) Can be documented with pictures and/or video, (3) Teach a skill through doing it.
Here's a link to the 22 Badges. That page also has links to each of the 22 Badges:
If it hasn't been certified in 24 hours, click the button on your post saying something like, "Is my Badge Bit ready to be certified?" If a staff person replies back with suggestions on how to fix it (and we've all had that happen!), fix the thing, and make a new post!
Go to the Badge Page and Post Links to Your Completed Badge Bits
Once you've completed all your Badge Bits for a Badge, go to the thread for that badge, and make a post that lists each badge bit and a link to your completed & certified Badge Bit. It should look something like this:
There are a few ways to find a direct link to your post. You can click the little icon on your post and then select any of those links. OR, you can right click on the little piece-of-paper symbol to the right of the date-stamp on your post. When you right click on that, you can then "copy link address." Then paste that address into your post! If you can't find any of those buttons because you're on mobile view, just post the link to the badge bit thread itself.
If no one has dubbed you with your new, shiny badge within 24 hours, click that button, because we're busy people and don't always spot new post in the PEP forum, especially if there's lots of new posts there!