Oleksandr Zinchenko is set to become the fourth edition to the Gunners squad after agreeing a move from Manchester City but Arteta says the club's focus will now be on outgoings.
The Spanish coach said: "We have a large squad so we have to make some decisions as well on the players that we're not going to be using consistently and be fair and straight with them and that's a process that is going to start very soon as well.
"We have a big squad and now we have to make things happen."
Zinchenko was in attendance as Arsenal beat Orlando City on their tour of the United States and Arteta has backed the player to add a "competitive edge" to his group of players.
He said: “There are still a few formalities to get everything completed but we're really happy to have him.
“I know the player really well, he's an exceptional footballer and he is someone that is going to bring as well another competitive edge to that dressing room.”
Zinchenko can play at both full-back and in midfield and Arteta feels that his versatility will be an excellent thing for the season ahead.
The Gunners boss said: “He was a natural No. 10 early in his career and we converted him into a left-back which can do a lot of things that we want in our way of playing.
“That versatility is something that is going to be important for the team because we have players in that position who are more specific full-back so I'm really happy.”