So i want to get the rusted look on my bay window

What is the best way to go about this? is there a way to allow it to rust then seal it?

She is my every day drive so unsure if it is a good idea to do it or not I just love the look! She is already lowered white walls on the way all I need is the rusty ratty paint job and i'm done! if someone could point me in the right direction please

If you want metal to rust wipe on a solution and salt mixed with vinegar overnight.
Then anchor wax it.
It all comes down to what condition you paint is in now though. that may help if you already have areas on the way out.
I personally have never seen anyone fake patina and succeed, but there is nothing saying you won't be the first.

Dulux do a cool paint. Available from Bunnings.
Hard work, but effective on curved surfaces like a bug...
My mate did an awesome job of it.