A mentor once taught me this framework about how to separate work and life. For many people this is easy - just clock off from work, then forget about it! But for some, especially those who are working in areas they are truly passionate about (e.g entrepreneurs), the lines between work and life start to blend. What are safeguards against overworking? This framework can help.
Create a ceiling on the amount of time I choose to work each day and week, and stick to it. It is better to consistently stretch myself slightly than to go through periods of extreme work, then crashing into a burnout period. Like sticky putty, consistently slight stretches creates the warmth that activates stickiness. Sudden extreme stretches causes tears.
If possible, I should define physical spaces to work, and separate it from spaces of rest. This seems to do something psychologically. I tend to associate place with tasks done in those places. It's the same reason I seem to concentrate particularly well in libraries, and why 'cabin in the woods' getaways make such a difference.
When I are not working, I should discipline my mind to not allow work to creep in. For a period, thoughts of work may come like flashes, that's okay. Notice them, usher them out, and stay present. They will slow down, and eventually stop breech my mind.
Boundaries of mind is by far the hardest for me. Boundaries of time and place are controllable because they can be accomplished with structure - e.g blocking my calendar, physically moving somewhere else. But training my mind is a lot trickier. I can do this in two ways: (1) fill my mind with something else, or (2) try to empty it out. I find that there is a time for both - the first is quicker & shallower, and the latter is harder but feels like a 'deeper cleansing'. There are rhythms that can be established to do this well, such as Sabbathing ([[sabbath is a gift, but it takes sacrifice]]).