Painting a metal garage door

[landmapper]

Hello everyone:

I am hoping to get advice on how to paint my garage door. Its aluminum with the wood texture and appears to have been originally powder coated from the factory or with some form of maintenance free application. The (white) color is in perfect condition. I want to paint it a different color to better match the new paint on my house.

Do I use a primer on top of the original paint?

Somehow sand it? Not sure its possible with the texture.

What paint type should I use? Enamel?

Will it eventually rub off on the edges from opening & closing?

Thanks,
Bryan