Keep everything you use to create a video project (Camtasia video and audio recordings, images/PowerPoint slides, music files) together in one folder. Each project should have its own separate folder.
If you have 2 monitors available, think about using both: in Camtasia you can have the Editor on one screen and the Timeline on another. A second monitor can also be handy for displaying your script while recording audio. You can edit just fine, though, if you use one monitor.
Try not to feel rushed while editing. The process takes time at first, but you'll get better & more fluent with practice.
Watch & listen to your video all the way through before starting to edit to give yourself an overall sense of what happened during recording and to develop a sense of what you want the final product to be.
Save your work. If you think that you won't remember to save after every edit (a best practice), do come up with a system that works for you--don't wait to save your project until the end. Check to see how often (or if) the video program you're using automatically saves your work. Remember that programs can crash, operating systems can go haywire, or you can just forget to save. You don't want to lose lots of work (trust us on this).
Planning
Production
Some suggested equipment for producing video tutorials; there are many more products that you can successully use in creating videos.