So... I usually plan my hat projects around the colors. What I do is choose the bright, warm, stimulating colors ranging from reds to yellows for hats to be knitted during the day, up to early evening. Then I switch to another hat project that's using yarn made of greens to purples/violets, or beige, or black... colors which are either neutral or cool and "depressing," to prepare my energy for ending the day.
I am almost finished with two such pairs: First, is the orange hat I promised to knit for my youngest sis Marie, although she did want it with blue... I'll probably knit her another one, since this is all in orange, as the design, for me, was best done in one color. The orange shade is a muted, more like "bright peach". This one I knitted daytime. I experimented on a rib pattern called the "arrow rib" and will post pattern soon:
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Second is my "evening" project, another one from my jumbo ball of variegated yarn featuring green, blue, light yellow and violet. I was able to figure out the best pattern, using stockinette only, that would make the colors "pool" together in interesting combinations. Two "pools" had the light yellow beside the violet in nice contrast:
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While another "pool" had the yellow surrounded by green:
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Since I've been enjoying the "pooling" patterns produced by the variegated acrylic, using 81-stitch stockinette rows at an exact number of decreases to shape the crown, I might use other variegated yarns.