This one is an excellent description of critiquing photos.
Check to see if you have any of these bad habits.
This is a great video that takes you into a traditional dark room and shows you how the old-fashioned processing techniques that predate Photoshop were done; dodging, burning, feathering, etc.
From one of the masters of Lightroom, Scott Kelby, comes "10 Things I Would Tell a New Lightroom User"
Here's the link to #10 but at the bottom are links to all the previous tips.