For every 1 quart of water, add 4 tea bags or 1 tablespoon (8-10g) of loose-leaf tea. Combine the water and tea into a resealable container and place in the fridge, steeping only for 5 hours for the best flavor. After 5 hours, remove the tea bags or strain.
If you want to sweeten your cold-brewed tea, make a simple syrup. This will allow the sugar to sweeten the tea rather than just collecting on the bottom of your cup.
Simple syrup: combine equal parts of sugar and water (e.g. 1 cup water to 1 cup of sugar; yields about 1.5 cups of simple syrup) in a saucepan, and heat on the stove until the sugar has dissolved completely. Let it cool, then add to taste your tea. You can also get creative and add flavoring to the simple syrup by adding fresh herbs or other ingredients after the sugar has dissolved and you’ve removed the syrup from the stove. For example, you could add mint, rosemary, ginger, vanilla, or citrus peel. Let the extra ingredients steep in the syrup while the syrup cools, then remove (leaving in the flavoring ingredients will shorten the syrup’s shelf life).