I've always been quite confident of colour, not in a self-conscious show-offy way (at least I don't think so), but in the same way that one would be confident about breathing. You don't think about it; you just do it and it turns out quite well.
Colour in beading isn't always quite like that. The proportions and the finishes and the reflections off the other beads add a level of complexity that sometimes defy over-thinking.
Often I do best when I'm trying out a design, seeing how it will work from my sketches, and I just grab whatever's around, and more often than not it turns out so much better than when I start from a fixed point and try to come up with a plan.
Take these three beaded beads. I had dark iridescent faceted beads, and I wanted a seed bead overlay.
I knew I wanted something bright and metallic for the centre (it worked so well for the first set I made), something silver-lined or copper lined, not too bright for the little adjacent accents, and something in a matte rainbow (sort of multicoloured) for the main seed bead overlay.
The first combination is the leftmost.
The metallic magenta are exactly right, as are the copper-lined olivine, but the overlay is too close to the faceted beads (the difference in finish is somewhat exaggerated in the photo; in Real Life there's less distinction), and the larger bronze seed beads at the intersection just disappear.
Next iteration I went for more contrast, with a blue-violet main seed bead, and size eights in a gilt-lined peach, ugh no! Gilt lined lavender! The whole is just a tiny bit nauseating, in much the way that the Magic Kingdom is.
The one I like the most photographed the worst. The main seed beads are a smokey lavender (more purple, less smokey than they appear), and the intersection beads are a medium-pale copper. Something golder would have been better, but my golds are either too dark or too bright, and this one is better in real life than in the picture.
It's a little disconcerting that it took three tries to get something that I didn't feel the need to attack with scissors (the first two are not long for this world, I can tell you that).