Spiral rounds with double crochet and a clean color gradient

Hi everyone,
How do I create a clean color gradient in spiral rounds using double crochet stitches?
Thank you very much 

With spiral rounds using double crochet, you’ll always see the color transition because of the difference in height at the round transition. That’s why you close each round with 1 slip stitch and start the new round with 3 chain stitches. When changing colors, pull the new color through in the slip stitch of the previous round.

Alternatively, you can switch to the new color in the last stitch of the previous round. This means you only complete the last double crochet halfway, and when you pull up the yarn for the last time, switch to the new color and pull it through the remaining loops on the hook.