One of the best ways to do this is to keep a daily detailed time agenda, and include time outs for leisure. When making your agenda, exclude anything you think will be too much. Always prioritize yourself as your first concern and client from the standpoint of your need for time for yourself to rest and refresh.
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Also, restrict or eliminate caffeine, sugar, and heavy foods.
And get plenty of rest, getting to bed before 10pm if possible. After this time the mind goes into overactivity, causing stress, anxiety,and junk food cravings.
Hope this helps