I do this for our PTA. I think if it more as coordinating than chairing. Top tips are be realistic in what can be achieved, ignore the moaning - for some people nothing is ever good enough!, don't commit more time or energy than you can manage
This. I did it when no one else would volunteer. I was pretty clear:
I would do it with a co-chair who could do more of the active volunteer-getting stuff, but I was happy to chair meetings, do admin-type official name on the newsletter stuff, and no more than 3 evening meetings and 3 afternoon meetings a year.
Year groups organised events amongst themselves. If there were not enough helpers for events they would be cancelled. The responsibility was shared in that sense. Lots of people are really happy to help but do not want their name down 'officially', so if you can utilise that it works. An events committee that reports to you is another way of doing it.
The school is extremely supportive and keen for the PTA to succeed so provide support to pretty much everything suggested.
The secretary and treasurer ran the banking, so never needed to do that.
I think if you are really clear what you can give - and stick to it, don't get guilted into more - then it is possible. I'd ask for a co-chair, though.