Here are some things I practise when facing challenging situations:
1. Make a full list of all the different projects that need to be completed.
2. Break each down into a list of tasks (with deadlines if relevant).
3. Break those down into: (a) tasks under your control (b) tasks where the ball is in someone else's court or awaiting some external event.
4. Each morning, before you launch into the day, pull into the to-do list for the day all of the '(a) tasks' that must be done today; also pull in '(b) tasks' where you need to chase people up.
5. Turn the rest of the tasks over to the universe; they'll still be there tomorrow, and the fact they're written down means you don't need to keep them in your mind. Focus only on the task at hand.
6. Proceed with the tasks of the day. Move slowly from task to task. Rest in between. Keep turning everything over to the universe. It literally knows what it is doing.
7. If you complete the 'musts' with time to spare, return to the lists and pick off a few more tasks to do.
8. Eliminate any projects, tasks, interactions, or people that are not mission-critical.
9. In free time, minimise highly stimulating or enervating forms of entertainment. Find ways to relax that regenerate rather than numb out.
10. Regularly stop for 5 minutes (or longer at weekends in the evenings), turn off all devices, and let your soul catch up. Concentrate on slow, deep breathing.