5) Back-up important files to a external location/drive
All of the above tips will help in a software crash, but will do little in the event of a hardware crash (eg disk-head crash, surge, etc) It is best to back up important revisions of your files to another drive, separate from your machine. In this case, if everything goes up in smoke, you'll still have your files. This happens more than you'd think. ctbram, above, has had more than 6 hardware failures in the past year or so. Good methods of backing up are with external hard-drives, USB thumb drives, or cloud services such as Dropbox or AWS.