Rinse the rice in cold water, then soak it for 30 minutes.
Cook the rice in accordance with the package directions. Note the tips and tricks for making the perfect sushi rice in the blog above.
When the rice is finished cooking, it should be fluffy, but firm. Each rice grain should still have its shape.
Cool the rice by spreading it out on a baking sheet.
While the rice is cooling, bring the vinegar to a low simmer in a small saucepan. When simmering, add the sugar and salt and whisk the solution until the sugar and salt have dissolved. Remove the solution from heat and allow it to cool slightly.
When the rice and the vinegar solution have cooled, gently fold the vinegar solution into the rice using a wooden spoon.
Refrigerate the rice until its ready for use.