Smith was thrown straight into the starting role with the Jets last season after veteran Mark Sanchez sustained a campaign-ending injury during pre-season.
The 23-year-old struggled at times as he made several errors, but he has admitted that he feels more confident going into his second year in the league.
"There's no comparison," Smith told reporters. "Last year I was a rookie. I was learning. I'm still learning, but I was learning the offense.
"I know the offense. Now, it's about perfecting it. There's really no comparison. It's completely night and day."
Smith threw for 3,049 yards along with 12 touchdowns and 21 interceptions in the 2013 season.