Four moves for catching it before it costs you the job you just started, not a general essay on work-life balance.
01
Notice the specific symptom, not just the feeling
Dread before 1:1s, snapping at small things, checking out during meetings. Naming the specific pattern makes it easier to address than a vague "I'm tired."
02
Audit where your time actually goes for one week
Most new managers are shocked by the gap between where they think their time goes and where it actually goes. You can't fix a load you haven't measured.
03
Find the one thing only you can do, and protect it
Everything else is a candidate for delegating, deferring, or dropping. Most new managers protect the wrong things by default: the urgent, not the important.
04
Say the quiet part to your own manager
"I'm underwater" is not a confession of failure, it's information they need. Most new managers wait too long to say this out loud.