Here is the arrow with the four bands of colour applied. The edges look pretty crapola, but that's fine - I've purposely not quite touched them.

Below, we can see the magic - the final thin crimson bands applied with a No.1 brush which neaten the whole thing up.

The blue is quite dark - as it should be - and doesn't show up well indoors compared to the black. It's a bit more visible in the sunshine we're all hoping for this summer!