The French face England in the final next Sunday at The City of Salford Community Stadium.
Baitieri told Sky Sports News: "We need to improve a fair bit.
"England have got a very good side and a lot of spark in attack so we tried to concentrate on good defence and to try to build pressure with our attack.
"We'll do a bit more homework this week. International football is not like the Super League, they're one- off games and you need to perform for the 80 minutes."
In the final round-robin match yesterday, England beat France 44-6.