I learned most from the long distance sub forum. I'm not knocking the others mentioned, just adding that long distance is also worth checking.

Nutrition is a key element. Supplements (like Endurolyte, or Eleet) will help you feel and perform better on the bike, and recover faster with fewer issues.

I used to do a 30 mile r/t commute for several years, and I found that varying intensity helped a lot. I would ride a time trial and then an easy day, an 'interval' day (not *real* intervals..) and an easy day, back to back steady pace days...

You can take the stress out of fighting the wind by spinning faster in a lower gear, at a lower speed. In fact, spinning faster, rather than grinding in a high gear, is always more effective and easier.