I first used a small string and a black pen to mark the edges of the spokes (to make sure they all have the same length).
Then I used fine masking tape to mark the contours of the flower, and covered the rest with bigger tape.
I scuffed the remaining areas with a red scotbrite (but I don't know if it's the perfect grit for the job).
I degreased the wheel to the max, and painted it several coats of Motip aerosol paint. Some people put primer first, but the paint still holds after more than 5,000kms of (mostly dry) road use.
I'm not a fan of the 'shiny' look so I used matt black (even semi-gloss was too much). It gets dirty quicker apparently, but wheels should be washed regularly anyway!
(Yes, I know, the wheels were dirty when I took these pictures. Duh
)
This is a 5,5. Originally, the wheels were painted by being lowered in a bath (I believe), so that's why the edges of the spokes must be as horizontal as possible.
Could have done better here...
I also means the 'inside lip' (or whatever you call it) needs to be partially painted too, at the same level as the spokes. Many people leave this area completely polished (I see Sander did the same), but painted just looks... just... more... well... original!!!
Another view of the small polished part left on the inside of the rim (about 5mm wide). It's much bigger on a deep 6.
And then there's the choice of nut finish (chromed or black). Don't get me started on that one...