The Brazilian forward swapped life at Chelsea to move across London in the summer on a free transfer and is already a regular feature in Arteta's side.
"It's been a cool, new experience. I hadn't worked with a coach with that mindset," Willian told Globo Esporte.
"The positional game doesn't mean that you have no freedom on the pitch, you have the freedom to move, but many times you have to respect the position, what the coach asks, the instructions, understanding that it'll be better for the team.
"It may happen that you don't touch the ball and get frustrated, but Mikel always says that, wait a minute, the ball will arrive. I've been learning a lot."