Root's 124 in the second innings came at a crucial juncture for England who had conceded a first-innings lead of 46 and were then reduced to 109 for four.
Having implored his team to play bold and courageous cricket in Sri Lanka, where England had not won a series since 2001, the 27-year-old then showed how to do it on a turning track.
A nimble-footed Root often danced down the wicket and used both the traditional and reverse sweep shots to negate the Sri Lankan spinners, hitting 10 fours and two sixes in his knock.
"I'm really pleased to back up everything I've spoken about and the way that I did it," Root, who was adjudged man-of-the-match for his 15th test hundred, told Sky Sports after his team won the test by 57 runs.
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"It's nice to make a big contribution but the thing that sits well with me is the manner in which I did it. I asked the guys to play a certain way, and I went out and backed it up myself."
England's series win in Sri Lanka was their first in Asia since their victory in India six years ago.
England needed three wickets on the final day in Pallekele with the hosts also in with a chance for a series-levelling win as they required 75 and had the dangerous Niroshan Dickwella still at the crease.
"We were pretty confident," Root said. "We knew we'd be able to create three chances on that surface, but we also recognised that when partnerships developed it became quite difficult.
"We tried to stay as calm as possible, trust all the plans we had, and follow through on that, and thankfully it paid off."
The England captain also had special words of praise for wicketkeeper Ben Foakes, who replaced injured Jonny Bairstow behind the stumps for the victories in Galle and Pallekele.
The 25-year-old was not only impressive with glovework but also made crucial contributions with the bat, hitting a maiden hundred on debut and following it up with an unbeaten 65 in the second innings of the second test.
"Foakes has made it look a lot easier than it should look, both keepers have," said Root. "Both stood back and up, with the ball not carrying at times.
"It's been spitting, keeping low, but he's done phenomenally well, and makes it look a lot easier than it is which is fantastic to have as a wicketkeeper.
"His runs have been fantastic as well. His demeanour out in the middle is one of someone who has played a lot more than he has. He has a great attitude towards learning and improving himself."
(Reporting by Sudipto Ganguly; editing by Amlan Chakraborty)
