Share 'How to choose the right needle for your fabric?'

Does anybody know a good guide about how to choose the right needle for your fabric. So far I have worked with standard needles, Jersey/strech needles and demin needles. But how do I choose a needle for a mixed fabric like a cotton/strech mix? And what needle do I use when I want to sew two diffrent types of fabric toghether? Is there a rule? How do you do it, do you use book or online guide or d…