Here’s a free online book that provides 97 short and extremely useful tips.

The tips are written by some of the most experienced and respected practitioners in the industry, including Uncle Bob Martin, Scott Meyers and many more. They encourage you to stretch yourself by learning new languages, looking at problems in new ways, following specific practices, taking responsibility for your work, and becoming as good at the entire craft of programming as you possibly can.

The entire list is a good read, however I really enjoyed the following entries:

#8: The Boy Scout Rule
#17: Comment Only What the Code Cannot Say
#20: Deploy Early and Often
#42: Keep the Build Clean
#68: Put Everything Under Version Control
#69: Put the Mouse Down and Step Away from the Keyboard
#82: Test While You Sleep and over Weekends

A print edition of the book is also available.