Ok, take a look at this. It was designed with some of our own group quirks in mind, so you'll probably want to use it as a baseline and modify it.
The "Concussion Hits" are setup so that you divide your normal hits by four and equally put them on the top four lines. The bottom lines are extended out more than you'd expect because we had a few characters throughout the years that could actually go that far down and remain standing (course they were in trouble after the fact unless we had a really good healer character).
Defensive bonuses are separated by type of attack and then what was contributing so that you could more easily calculate other defensive bonuses on the fly if you needed to.
Then you have all the things impacting your... what kind of penalties you might have from crits, how much you're bleeding or burning, spell casting penalties, how many rounds you've lost initiative, are stunned, down, etc.
Lastly you have 12 rounds worth of activity (which totals up to two minutes if you're using 10 second rounds). % Act is in case you have something giving you bonus action (like Speed), what your total initiative is, declaration seconds for each phase, who your target is, who you are shielding, how much you've put into parry, if you have any bonuses or penalties to hit (a temporary one from something like a critical or paladin inspiration spell).
Let me know if you have any questions.