PKHeX has been officially updated to support Sun and Moon.
projectpokemon.org was ironically hacked, it's databases trashed. If you had an account there, and you used the same password for other sites, change it immediately.

>HOW DO HOMOBREWß??
http://www.3dbrew.org/wiki/Homebrew_Exploits

>HOW DO INJECTORZ????
The most straightforward way is to use a homebrew save dumping tool like JKSM, and use PKHeX to edit the file itself.

>HOW DO CFW???
http://plailect.github.io/Guide/

>SUMO BANZ???
It's unknown if using the leaked dump online now will result in a ban. If you want to be safe, delete the Sun/Moon title and titlekey via FBI, then install a proper eShop dump via your method of choice. Remember to back up your save file, and if you can't inject it into your new eShop dump, then get to a point where you can save in game and try again.
If you're already banned, then ¯\_(ツ)_/¯

>IN-GAME INJECT$?? QR CODES??? NO OUTLINES????????
https://github.com/SciresM/SMPatcher/releases
Pre-patched codebins: https://mega.nz/#!nQUDwZQJ!LYEszSk-7_Fx7srnSU9PGQjoSjZT2SflRhMyAEsxj4k
>Luma
Just copy and paste one of the patched code.bins into SD:/luma/code_sections
Hold select when booting Luma to open up the config menu, turn on "Enable region/language emu. and ext. .code" and press start
>homebrew (n3DS only)
Extract the patched code.bins and rename them to 00175E00.code for Moon and 00164800.code for Sun.
Place it in SD:/hans/
Start up the homebrew menu and open HANS, open Pokemon through it.

>OLD instructions on how to inject and general info (DON'T BE A LAZY FAGGOT, READ THIS)
http://pastebin.com/SYAcZLNQ
http://pastebin.com/FWSxVMue (for web exploit users)

>For ROM-hacking stuff
http://pastebin.com/zmH9KsGd
>If you want an injection, follow this guide for how to request or don't post at all. Only ask for Sun and Moon.
http://pastebin.com/1CgssPrV