Sir Alex Ferguson would sit us in a room and we would watch our forthcoming Champions League opponents on video.
It often did more harm than good. We would watch teams like the Juventus of Zinedine Zidane, Alessandro del Piero and Edgar Davids, and leave wondering how on earth we were going to avoid losing to a team of 11 Peles.
Then it stopped.
After several near-misses in the Champions League when we blamed everyone but ourselves for not reaching the final, we started to prepare for games differently in the 1998/99 season.
We did not study video and the manager talked more about us than our opponents.
His thinking was that we were at our best when we played like Manchester United should: when we attacked teams and went for victory from the first minute, not when we worried about our opponents by watching their highlights.
No, instead we would let them worry about us.
He knew, too, that his players were more experienced, and that our understanding of our opponents had grown.
Playing Champions League football year in year out gives you that experience and confidence.
I also think he increased the number of scouts and employed his brother, who would spend his life on a plane as he travelled to watch our forthcoming opponents. He trusted what his brother told him.
United immediately began to play with more confidence.
We went to Camp Nou and attacked Barcelona. Ferguson said that it had always been one of his dreams in management to go to Barcelona and attack.
We realised that for him in a superb 3-3 draw.
Five years earlier United had been beaten there 4-0. I know they were missing players, but the mentality changed at the club throughout the 1990s.
In my first year, we were knocked out of the Uefa Cup by Rotor Volgograd. In my final years at Old Trafford we won the European Cup and went to places like Real Madrid confident that they feared us more than the other way round. I look back at some great moments, but also with regrets.
Regrets that we did not reach three Champions League Cup finals in four years like the current team.
We were certainly good enough, but we were deprived by a moment of luck or genius by Fernando Redondo or David Trezeguet.
And by sides who I genuinely think were better than the teams now.
There is no way a team as weak as Schalke would have reached the semi-finals in 1999. Italian football was much stronger then and the Champions League was a better tournament for it.
Juventus were a magnificent side. So were Inter and AC Milan.
Spain had more depth, too. The Valencia of 2000 were far better than the Valencia of 2010 and Deportivo La Coruna were a great team.
The German squads such as Bayern Munich were extremely difficult to play, season after season.
The current Barca side is arguably better than all of them, and they only have to play to their strengths to beat anyone, including Manchester United.
I do believe no team in the world can stop Barca when they play well. And they do that consistently. They've met challenges from teams such as Real Madrid and Arsenal by wiping the floor with them. They were told that Shakhtar Donetsk were a potential banana skin in this season's quarter-final and they hit them for five.
They meet their challenges head on and that's why they were clear favourites to win the European Cup this season. United were only the fourth favourite, but the team has done very well to reach the final.
United need to play to their strengths, like we did, and attack without fear.
You might laugh, but if United sit deep then Barca will dominate possession and, in all probability, score more goals.
It is easy for me to say that United should attack.
Granted, we tried that in the 1999 final against Bayern and failed. Football can be like that. I thought my mental and physical preparation was perfect, yet I didn't have a good game. Many of my teammates did not, as well.
Our plans went out of the window when Bayern got an early goal, just as United's did when Eto'o scored after nine minutes in Rome in 2009 final.
We nearly lost the 1999 final after one of our worst performances of the season. That would have been a great shame, considering how well we'd done in Europe, but then we had a bit of luck.
And every team needs luck.
United needed it last season against Bayern Munich and didn't get it, but there have been moments in United's season where a late goal at Stoke City, or home to Wolverhampton Wanderers, Everton or Bolton Wanderers, have provided a turning point.
United need 11 heroes at Wembley Stadium tomorrow.
And just that little bit of luck.
Andrew Cole's column is written with the assistance of European football correspondent Andy Mitten