Manning recorded a career-high completion percentage of 62.9 in 2010, but that figure dropped to 59.9% last season - his first year below 60% since 2007.
The 32-year-old believes that such figures are vital to the Giants' success due to the fact that they attempt a lot of big plays.
When asked what he is hoping to improve on in the upcoming season, Manning told reporters: "Completion percentage. Being more accurate and better on our deep balls. Our big plays were down last year, and that's a big part of our offence.
"We're going to use play-action, we're going to get the ball down the field. We're not scared about pushing the ball down the field. But it's good when it pays off and you hit big plays and game-changing plays.
"Last year, I think we had opportunities to hit them and we just didn't hit them. So I think that's what we've got to get better at, is just kind of connecting on some of those deep balls."
Manning was then asked how he planned to go on about improving that stat, and his response was simply to practice.
"Just throw them," he said. "Just throw a lot of them. I think a big part of it is not having Hakeem [Nicks] at full strength and full speed. We didn't have him on many big plays.
"Victor [Cruz] does a great job in the slot, and we have Rueben Randle and Louis Murphy on the outside now. But some of it is just me throwing the ball more accurately so a guy can catch it and run and take a 10-yard pass and, because it's accurate, turn it into a 20-yard, 30-yard gain. So I think you've got to keep throwing them with that faith that your guys can go get them."
Manning threw 26 touchdown passes and made 3948 passing yards last season, his lowest tally in both categories since 2008.