I keep them in folders. I have 4 folders which are 2 folders of 10 9 pocket pages, 1 folder with 14 4 pocket pages and a binder. I organise them by which theme deck or
booster pack they came from and then I organise those by the types of pokémon and trainer, support and stadium cards are organised alphabetically. If I have pokémon in the same evolutionary family which came from different booster packs or theme decks I do switch the cards' places to have the evolutionary family in a row together. I also put the movie promotional cards close to each other and put the
Eevee evolutionary family close to each other in national pokédex number order with some energy cards of its type above each one in my 4 pocket page folder because I do have at least one of each of the 7 evolved forms of Eevee and many Eevee basic cards.
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