How do you use content aware fill?

There are 2 ways to use content aware fill in photo's. If you want to fill in spaces left by lets say tilting the photo to the right angle, select the transparancy with ctrl+click and then go the the select button (top of the program) and choose inverse. From there Go to select again and this time choose modify, and then choose expand. Try to make the photo overlap the spaces by choosing a high expansion (say 10), then press shift+delete key to open the content aware fill and then press okay. Take away overlapping distractions from a photo, you can either use the spot healing brush tool and choose content-aware at the two bars under the top of the program and erase away.