I'm having the hardest time mastering sheet metal. On the project I'm currently working on I drew the outline of the parts, and then drew in the bend lines and just used the fold command. That seemed to work pretty well for the most part. I'm now on another part, and I kept getting errors when I was doing it that way, so this time I tried starting with a face and just adding flanges all over it. It seemed to create the part okay, however it won't unfold.

Maybe I'm doing this all wrong anyways.