There's really no cure for the flu but once you have the flu you can do some things to help you feel better and speed up recovering with the flu.
When you have the flu you should stay hydrated, get plenty of rest, take some pain medicine to help with the body aches, and breathe in steam to help keep your lungs and throat moisturized and keep them from drying out.
Drink some Pedialyte as well to help keep your electrolytes in place since when you're sick with the flu you can lose some electrolytes which needs replaced.
You can also take a steamy hot shower which can help wash germs away from you and the steam from the shower can help your throat as well and open up your pores.
Be sure to get a flu shot before you get the flu as well because it can help prevent the flu and even make you feel much better sooner.
And take some flu medicine as soon as you feel the symptoms of the flu coming on such as fever, chills, body aches, muscle aches, etc