PersonSP
Writing- 'n-Drawing-aholic
Towns Folk
Hey! I feel like @Alex is giving you a bit of a harsh treatment. So step by step:
If you want to sell a pokémon, state which (you did
), for how much pc (you did ) and if they are shiny (they are) they must be from generation 6 (So either Pokémon X&Y or Pokemon Omega Ruby & Alpha Sapphire) and you must proof you caught them yourself (so we know they aren't hacked). You do that by making a picture of the pokemon you're trying to sell and also making a picture of your trainer ID (on your trainer card). If the pokémon has the same ID as your trainer we know you caught it. 
Just so you know, selling hacked pokemon can get you banned, so be careful to sell only 'legit' pokemon. Good luck!