I used a product called ReNu Pro, I bought off of Amazon.
This product worked very well and it did last several months and went through several washes too.
Like others here, follow the instructions.
I even wore the gloves and I am glad I did.

 

And here I was all happy that my pillar plastic had turned to a shade of gray that matched the paint color pretty closely. Dang, black and new or gray and stealth? lol

 

I have to try one of these products. I've been using Meguire's Back To Black for some time. Not overly happy with it.

 

I used it. Love it. You can get it at Walmart. Not cheap. About $20 for a minuscule 3oz, but it is enough to do the whole car and it lasts. Even comes with a headlight applicator. I didn't need it on mine so I can't tell you how well it works for that.