Choose a brand of ginger ale based on how sweet or gingery you want it to be. A brand with real ginger, like Boylan ginger ale, is great for a nice, soothing tea.
When it comes to the tea, ginger tea is an obvious choice. For something on the caffeinated side, black tea is perfect, and it's still tasty when it cools down.
Simply microwave the ginger ale in a mug for a minute or two or heat it up in a pot on the stove. Once it's good and hot, just drop in your tea bag or loose-leaf tea.