I read a book that was pretty good on this topic.
It said that you can see burnout as a long-term fail in the strain--rest equation, much like obesity is a fail in calories in--out.
Sometimes, it's hard to change the strain part, since strain may be something that cannot be changed by you (eg worry about family or society), or it is a sum of infinite tiny things that are individually insignificant even if you got rid of a couple. In that case you need to change the rest part.
Rest, as expressed in that book, is not necessarily being passive, ie lying on the sofa watching TV. It can be, but often, it's rather the opposite - it's stopping you from _real_ rest.
Rest can be seen as a change in what you do, on a mini-scale. Ie, it's not "change job and move to another country", but it can be to not do the same thing for too long.
Example: you work on the phone, talking with people as support or whatever. Rest in that case is not to put down the phone and chat with friends. Rest would be to change the mental occupation, eg meditating, sorting papers, doing something admin-y. For some, offloading to friends after a days work is a rest, for others, that's a strain. You need to introspect here.
A couple of things anyone can do that will help a great deal:
* Go to sleep in time to get a full nights sleep, for most ca 8h
* no drugs or alcohol, since that'll impair high quality sleep
* use a pomodoro clock or kitchen timer to remind you to take breaks every 30 minutes or so of work
* remove all time-sucking apps from your phone, eg facebook, youtube. No excuses, you don't need them. For eg browser on phone, use eg "Digital wellbeing" (android) to limit yourself.
* install Leechblock on your browsers, which, again, blocks timesuckers
* exercise! Getting your pulse up often is more important than that weekly 2h weightlifting thing. Ie, do burpies a few times a day. Use the stairs. Take walks.
* periodically (eg every 15-30 minutes) close your eyes and breathe deep and relax. A fitbit can help with this reminder.
Don't beat yourself up if you have bad days, it's a long-term change in behavior and changing it doesn't happen overnight.
Note that excessive procrastination or compulsive timespending on eg youtube or facebook etc, can be a sign of mental exhaustion and you try to stimulate yourself to be more awake, like a dead tired child that is just all over the place. You need to make such things harder to do (remove apps etc) and good things easier to do (eg breaks).
Related: if someone knows of something like Leechblock but for Android and apps, that would be awesome. The Google "Digital wellbeing" is just bad. Leechblock makes it easy to block and hard to unblock, DW does the opposite.
edit: went to https://www.android.com/digital-wellbeing/ and omg, it's designed like by a tired child on speed. Large letters flying in from all over the place, really horrible.