Sooner or later your laptop will spontaneously combust or get left on a train. Work on the basis that this could happen at any moment.
Store your actual work in a central location (company server or cloud) rather than having the only copy on your computer. This also goes for any important data that you have collected.
Ensure that you can recreate your machine with the minimum of fuss. I have had complete laptop failures twice, but thanks to the magic of Apple’s Time Machine I could just buy a new computer, plug in my backup disk and in a few hours I had a working computer with all my software, settings and data restored.
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