I am just doing it like this: starting with a 90 second expoosure (which I have worked out from earlier experiences as a good ballpark starting point), fstop 8 and most of the time I do one negative only in a session.

When I've gotten the size of the print that I want down, say a 17x23 cm on 18x24 paper, there are two variables I work with, the exposure time (longer or shorter) and the temperature, and then I just snatch it when it looks good. Eyeballs and brains and simple as possible.

I started out doing test strips but I found out that it was a waste of my time, especially as I do detailed notes of exposure time, developer temp, developing time and paper and whatever extra I need to know to do another print in the same style. The dilution always stays the same.