The concept was to use Lego colours, or the nearest matches I could get. I went to the local paint place with yellow, green, blue, red and orange bricks, and asked if they could colour-match to them. Amazingly, they managed with red, blue and yellow, but the green and orange were too shiny, so I had to find the nearest match manually - fortunately, the orange matched pretty closely with paint we'd already used for some highlights around the house, and there was a good green there as well. All the white is done in a colour called "nearly white", which we'd also used around the house in various places. And finally, it got a clear gloss acrylic finish over the top, because the matched paints only came in matt.
It started like this ... well, this pile actually has parts for two bookcases, the other got made and stained and put in the library:
Here it is, built but unpainted:
After getting a coat or two of paint (different colours needed different numbers of coats, particularly the yellow, which ended up with five or six!) :
Then it all got two coats of a clear gloss finish (since I couldn't get the Lego-matching colours in gloss acrylic paint) :
And finally it was done, and is in use with various books and Bub-related items in it :
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