The Latvian, 20, hit 54 winners on her way to a "dream" 4-6 6-4 6-3 win over Romania's Simona Halep.
"I always had the possibility I could hit the ball really hard. If I have a chance to go for a shot, I'm trying." said Ostapenko.
She is the first unseeded woman to win the French Open since 1933. It was only her eighth appearance at one of the four tennis majors, the fewest by a champion since Maria Sharapova won Wimbledon in 2004. A 100-1 outsider at the start of the tournament, she will rise from 47th to 12th in the world rankings following her spectacular victory.
Ostapenko chose a tennis career over ballroom dancing, something she still practises four times a week. And it was the 299 winners she hit over the course of seven matches that captured the imagination of the Roland Garros crowd, who roared her to victory on Saturday.
"Nobody taught me, it's just the way I play. And also I think my character is like that. I want to really hit the ball," said Ostapenko.
Ostapenko beat Olympic champion Monica Puig, former finalist Sam Stosur, former number one Caroline Wozniacki and two-time semi-finalist Timea Bacsinszky on her way to the final.
But it was not until the closing moments of her win over third seed Halep, the 2014 runner-up, that the Latvian contemplated winning the title.
"I think I was up in the third set 5-3, then I realised I can win the match. Not before that. I was just taking it step by step," she said.
Having earned a total of £1m in her professional career before Roland Garros, Ostapenko, who turned 20 on Thursday, will take home £1.65m for Saturday's victory.
"I wasn't even thinking about it," she said. "I was thinking about winning the title."
The junior Wimbledon champion in 2014, she will now head to the All England Club next month among the contenders.
Ostapenko begins her grass-court season in Birmingham at the Aegon Classic, along with eight of the world's top 10, and will then head on to Eastbourne for the Aegon International.
"Of course I will probably now will have more pressure and attention, but I'm going to try to deal with that. I think it's going to be little bit difficult but I chose to be a tennis player, so that's my career. I should be fine with that," she said.