TL:DR:
>Complete all Trainer Challenges (Cheat Engine's speedhack to speed up AI games) to get 45 free packs.
>Play through using Basic decks to unlock them for versus play.
>Farm Versus Mode theme ladder for Tokens and Tournament Tickets.
>Enter tournaments to get TRADABLE chests and packs.
>DON'T OPEN THEM.
>Trade them for the cards you actually want for a deck you want to build.
>Public trade is like the GTS, if you want proper results, put up your own offers.

What themedeck should I buy?
>Buy the Lunala one.

Resources
>http://www.pokebeach.com/forums/forum/tcg-competitive-play.156/
>http://www.pokemon.com/us/play-pokemon/pokemon-events/championship-series-event-results/
>http://thecharizardlounge.com/decklists/

To see what your PTCGO stuff is worth, look on the forums in the trading section. Trading companies overprice cards, aim lower. Keep pack value in mind when trading.
>http://forums.pokemontcg.com/forum/33-in-game-item-exchange/

Code Giveaways:
>Post them as an image with the QR code covered. Bots will snatch plain text or uncovered QRs.
>Ask for emails and send em individually.
>Post your pulls faggot.

TOTT: How much do you think Shining Celebi and Shining Lugia are going to cost now that we know there's a chance they might not be in Shining Legends?