Color Change Decreases:
When you get to the decrease rounds of a piece that that has color changes in the middle of the work (e.g. a penguin), you might need to decrease when you get to one stitch before the color change:
You can just move the decrease somewhere else but this may be troublesome if you need to increase evenly or do shaping. You can also decrease the next two stitches using the current color and then switch colors afterwards but that might look weird depending on the design.
I like to change the color in the middle of the decrease. Pick up the first loop with your current color and then pick up the next loop in with your new color:
When doing decrease (or increase) rounds with color changes, you can also do the instructions about halfway through the round and then mirror it for the rest of the stitches to make it more balanced:
You can’t line up the color changes 100% when working in spirals since the stitches shift over but doing this will help the decrease rounds look better.
Crocheting Over Yarn Ends:
Instead of cutting the yarn and tying knots or carrying over long floats of the colors, just crochet over the ends! It can be more convenient when you’re doing a lot of color changes.
Also, if you don’t cut the yarn of the old color when crocheting over the ends and your next color change is that color, you’ll have it ready to go: