Follow the recommendations in your manuals
It may be hard to admit, but—believe it or not—the original manufacturer probably knows more about your motorcycle than you do.
Luckily, factory engineers are happy to share much of what they know about your bike in your owners manual. It will advise you on oil type, maintenance schedules, service procedures and more. Read it, study it, memorize it.
In many cases—especially if you plan to do more sophisticated maintenance—you'll also want a full-on service manual. The service manual generally includes everything a shop mechanic needs to know to rebuild every part of your motorcycle, plus stuff like hard-to-find torque values for every bolt on your bike.
A factory service manual might cost $40 to $100 or more. Cheaper options might include a shop manual from a third-party publisher, such as Clymer or Haynes.