The Western Sydney Wanderers midfielder, who was a part of the great Brisbane Roar sides that won back-to-back grand finals in 2011 and 2012, said the key was to treat it like any other game and aim to do the same things that got you there in the first place.
"That was a great team we had at Brisbane, with a lot of very good players on it, but I think it still comes down to who handles the pressure of the day the best," Nichols told The World Game.
"Both grand finals were tightly fought and we stood up at the right moment and took our chances and I think it's a matter of handling the hype and emotion of the day.
"The game, once it starts, seems to fly by, so you've got to be calm and stick to the game plan to be able to make the most of it."
Nichols said the then Roar coach Ange Postecoglou made the point to the players before the first grand final, against Central Coast Mariners, that they couldn't afford to wait for the game to come to them.
"Ange said to soak it all in leading up to the game, and then, when you get out there, make sure you try to impact on the game, because it really does go quickly and you need to get yourself into it," he said.
"I look back on both of those games with no regrets."
Both games were very dramatic. The first went to extra time at 0-0 and the Mariners looked home after establishing a 2-0 lead, but two late goals from Brisbane tied it up again at 2-2 and Roar went on to win a penalty shootout.
In the second, Perth Glory were up 1-0 with the game getting old, before Besart Berisha equalised in the 84th minute and deep into additional time, Brisbane were awarded a controversial penalty, which Berisha converted for a 2-1 win.
"The first one was a bit of a scrappy game," Nichols said.
"I came off about 10 minutes before extra-time. The second one I felt like I impacted on the game more, even though we left it late again.
"I just played my role for the team and continued what I had done all season and this Sunday against Adelaide will be the same. I won't change anything, because it has worked for us to get there.
"The best way is to just enjoy the occasion and play your role, because you don't need to do anything different.
"The team has been training hard and competing well all year to get to this point, so why change your game plan and the way you go about things now."
Asked whether he felt, with the experience of the first of those grand finals, he was better equipped to play in the second, Nichols replied: "I probably just knew the crowd was going to be very loud and the game was going to be high intensity for the first 30 minutes and then flatten out a bit.
"So you're more aware of what it's like when you've played in one, but I felt like I did my role in both of them."
Nichols was cited under Football Federation Australia's national code of conduct after Western Sydney's epic, 5-4 semi-final win over Brisbane at Pirtek Stadium last Sunday. He was pictured giving Roar fans a two-fingered salute after the game.
While he could face a sanction, Nichols was not required to provide a submission until next Wednesday, clearing him for the grand final at Adelaide Oval.
The most impressive part of Nichols's game this season is the fact he has always been prepared to take responsibility to try to make something happen when it is necessary.
He is an inherently unselfish player but if shooting is the best option, he doesn't hesitate to put his foot through the ball.
Nichols said he wouldn't be afraid to take responsibility to try to make something happen in the grand final.
"I think that's something that comes with maturity, you don't get fazed by the situation," he said.
"You just continue playing your game and get on the ball and hopefully create, and help the boys up in the front-line.
"That's my intention on Sunday, to continue playing and impact the score-line with an assist or a goal, and help the team the best I can.
"But on the day it could be anyone and we've got a number of players who can make that impact. You only had to watch our semi-final to know that.
"We were 3-0 down and Romeo Castelen stood up with three great goals when we needed someone.
"You've just got to keep a clear head, so that if you get in a situation where you can do something it feels no different to any other week. The crowd's going to be bigger and more excited, but you've got to stay cool, calm and collected."