Get enough rest
Getting enough sleep is crucial for anyone in any profession, but Ronaldo says proper sleep is especially important for training.
"I go to bed early and get up early, especially before matches. Sleep helps my muscles to recover, which is really important," Ronaldo tells British soccer magazine Four Four Two.
He tries to get a minimum of eight hours of sleep a night, but like most people before a big day, he has a hard time falling asleep the night before a match.
Fit in a short workout in the morning
Ronaldo says it's key to "fit it in exercise wherever you can."
"You can do an abs workout in your bedroom when you wake up in the morning or before you go to bed," Ronaldo tells soccer news site Goal.com. "If you get into a routine then it makes it easier, it will become a habit."
Eat small, balanced meals
"A good workout must be combined with a good diet," Ronaldo says. His general standard for meals is that they must be high in protein and contain plenty of whole grain carbs, fruit and vegetables.
"If you train regularly it's important to keep energy levels high to fuel your body for better performance," he adds. "I sometimes eat up to six smaller meals a day to make sure I have enough energy to perform each session at top level."
Psych himself up
When English soccer player Wayne Rooney, another one of the highest-paid soccer players in the world, played alongside Ronaldo for Manchester United, he noticed a ritual Ronaldo had before games.