Fishing

To fish, change your outfit to 'Fisher Outfit'. Then use the shortcut 'Ctrl + Z' and use in any lake or ocean (left mouse button), when some Pokémon take the bait, press 'Ctrl + Z' again.

New Pokémon appear depending on the bait you use and your level of fishing.

 

Hint: Baits can be bought from NPC Guru.