How can I learn custom color coding for beginners?

[Moowool]

Hi, i need a dummies guide to doing custom colours as i have never coded before and it seems very confusing to me.

i have looked at this article https://help.stylehatch.com/article/335-product-color-swatches but it looses me pretty fast.

Any help would be great as we dont have extra money to spend and we have thousands of products to do. 

thankyou