There is so much information in this world to help us become better stitchers and spinners. Here are a few of the resources that were the most helpful for us.
New! What is Grist?
https://www.masondixonknitting.com/grist-secret-measurement-substituting-yarn/
Learn to Knit http://knitpurlhunter.com/blog/?p=283
Life line in ribbing
Cutting your knitting
Yarn Weght Converson Table
https://www.laughinghens.us/yarn-conversion-chart