The striker signed a two and half year deal at Stark’s Park where he had previously had three loan spells from his parent club Hibs.
He said Raith Rovers are the “perfect” club for him.
“I’m delighted to be back and to have signed a long-term deal here,” he said.
“At the age I’m at I need to be playing games regularly and develop as a player.
“Even though I was training every day with some top class players at Hibs, it doesn’t compare to playing games week in, week out.
“It was the perfect time for me to move on and get something permanent and I think this is the perfect club for me to build my reputation, improve as a player and bang the goals in.
Gullan’s first start came on Saturday against Arbroath and whilst it didn’t quite go to plan with a 2-1 defeat, the striker says this weekend’s Scottish Cup tie away at Banks O’ Dee is a great chance to get back to winning ways as the club has now gone five games without a victory.
“It wasn’t great on Saturday,” he says, “the way we performed and the result made it a disappointing day but we have the perfect opportunity to bounce back in a big Scottish Cup tie this weekend.
“Hopefully we can get through to the next round and that will bring us our confidence back.
“We’re all looking forward to Saturday and if we can win then hopefully we can go on a run in the league and get ourselves moving in the right direction again.
“We’re the only ones that can change the poor run of form that we’re in and looking at the squad, we’ve definitely got the players to do that.”
The 22-year-old says the Raith squad are still determined to make a push for Championship title, despite the poor run of results.
“It hasn’t been going our way at the moment.
"Maybe our performances haven’t been as good as they were at the start of the season before I was here.
“Looking at the league table we’re only six points off the top and this league is so unpredictable as well that anything can happen.
“Maybe we can go on another run like the boys did earlier in the season.
“But we’re not thinking about the league just now and taking a week off from it is maybe a good thing.”
He added: “We’re just focusing in this massive game on Saturday.”