However you come by your Rupees, ensure you’ve got at least 30 of them, and then soar to Milk Road. Play Epona’s Song to call for Epona when you arrive, then ride her down the southeast trail to visit the Gorman Track.
Epona by a Nose
Ready for another race? Remain on Epona, and approach the mustachioed man in the blue overalls. 
-Target the man and speak with him from horseback, and he’ll challenge you to a race around his track. Pay the man 10 Rupees to begin the race. (If you’re a few Rupees short, return to Milk Road and use Deku Link’s spin attack to chop down the tall grass along the road.)
The key to beating the Gorman Brothers lies in using Epona’s sprint wisely. Tap 
every few seconds to make her sprint, and you’ll maintain top speed for as long as possible. When moving at top speed, Epona automatically jumps over low fences, giving you a big advantage. Just make sure that you don’t run out of carrots, or else you won’t be able to sprint for quite some time. Always leave at least one carrot at the bottom of the screen, and they’ll quickly come back so that you can keep on sprinting.
Keep to the inside of the track (close to the right wall) during the first turn, and then speed past the skinny trees. Stay to the right until you leap over a couple of fences. Avoid the trees and mud patches that follow, then get back over to the right and jump a few more fences down the final stretch. The finish line is just ahead, so spur Epona onward to victory.
Humbled by Epona’s speed, the Gorman Brothers reward Link with a valuable mask. If you feel like racing the Gormans again, they’ll reward you by filling one of your Empty Bottles with milk. This healthy beverage can be consumed twice, restoring up to five Hearts of life energy with each use. There’s no need to go for the milk, however—the Garo’s mask that the brothers give you is the real prize.
Garo’s Mask
You got the Garo’s Mask! The wandering ninja spirits who appear at Ikana once wore this.
Does a Body Good
If you still have a little time left before 2 a.m. on the First Day (when you need to meet Romani), soar back to Clock Town, save your game, and then leave town through the south gate. Head directly south, moving into a big hollow log. Place a bomb on the ground directly in the middle of the hollow log (cut tall grass to find bombs if you need some), and you’ll blast open a hole that leads to a secret cavern.
Drop into the cavern to find a couple of cows lazily grazing away. They’re a long way from the ranch, so whip out your ocarina and play Epona’s Song for them. The soothing sound reminds the cows of the pasture, and they happily fill one of your Empty Bottles full of nutritious milk. Get more milk by playing Epona’s Song over and over again for the cows.
Milk
You had your bottle filled with milk! Drink up for health and long life. One gulp recovers five Hearts. Even better, one full bottle has enough for two helpings. Yum!