Very sorry To hear about Eero this morning.
It seems there maybe a few of us that sail by ourselves. I don't do it all the time but have done some.

What are some things to do or try to remember to do to make it as safe as possible?

I tow a 50m rope behind me with a few knots along it to maybe grab if I can get to it.
I limit it my speed to 5 kts and as I don't have an auto pilot, it's always trimmed to come upwind If I have to let go of the tiller.
If I have to go below I de power quite a lot.
I never have a pss over the back.
i have a waterproof hand held VHF clipped to me and a personal epirb in a pocket.
Life jacket of course no matter how flat

others?