I’ve just picked up a cheapy Boardman CX frame from eBay for commuting/winter-biking/occasional light touring duties. It’s white., like this, but has no forks:

I’m planning on sticking the Kinesis DC19 forks on it that I currently have on my existing commuting/winter-biking/occasional light touring bike (which is too small, hence the purchase). They’re black shiny carbon with a few decals, like this:

I’d probably like to spray them white to match the frame, I assume it’s just a case of a light rub down with fine sandpaper and crack on? Or am I being oversimplistic?

I’m a dab hand at spraying with aerosol cans and have used them for sign making and restoring classic motorcycles. Not any more though. With the old cellulose cans it was possible to get a great finish but now that all the cans are filled with acrylic paint to make them safer, they’re really quite poor.
Your main problem will be the length of time each coat takes to harden off properly (weeks) and at this time of year it’s even worse. Baking it in the sun for a few days is the best method before lacquering over the top.
If the paints not fully hardened the lacquer can craze as they dry at different rates.
If your forks are in good condition, leave well alone or take them to a local spray shop to have them done in 2-pack.

Ah, okay. I’ll see what they look like when they’re on, decide from there (now I’ve looked at the pics side by side above, I think it’ll look okay)