Tennis ace Serena Williams — a four-time Olympic gold medalist and winner of 23 Grand Slam singles titles — admits relaxing doesn’t come naturally for her.

But the busy entrepreneur (whose ventures include a jewelry line, a clothing label, performance products and a capital fund) says her family is worth slowing down for.

In fact, the athlete’s perfect day means spending quality time with her husband, Reddit co-founder Alexis Ohanian, and their daughter Olympia, 5, at their South Florida farm.

There, they grow fruits and veggies, raise chickens and hang out with their mini horse, Daisy; steer, Antonio; and dogs Chip, Maximus and Adora.

When stress creeps into the multitasking mama’s day, she goes for a massage, a Lego-building session or a Marvel movie break.

If she needs a sounding board, she calls her sister, Venus. And if all else fails, retail therapy has a very calming effect. Here, Williams, 41, shares her best buys.