My "process" is pretty easy:

1) What's my "optimal defense frequency"?
2) What part of my range qualifies as bluffcatcher?
3) What's the optimal calling range, based on #2?
4) Any further reads?

For #1 I got to quickly estimate / calculate Villain's risk (pot vs. bet) to get my optimal defense frequency (MDF).

For 2) I got to roughly estimate the range Villain got to the river with (given actions and betsizing). Depending on that my worst bluffcatcher might be K-high, or bottom pair or TP or ... that defines the range that I got to "defend" (namely the range that #1 is referring to).

For 3) I got to calculate how many combos of my #2 range I got to defend. Then I am looking for those combos who have the best blockers (blocking his valuebets, unblock his bluffs). That's my "standard" defense range.

For 4) I check if there are any hints in Villain's behaviour, history, notes, maybe even poolreads that needs / suggests adjustments on my results. For example, I could skip the bottom part of my bluffcatching range (or stop "bluffcatching" at all), if I came to the conclusion that Villain (or the pool if unknown) is presumably never (or at least not often enough) bluffing on the river.

Obviously those steps do not necessarily be processed like an algorithm, one after the other, mostly it comes "intuitive" with training, especially #4 oftentimes overlays or even substitue the other steps. But in really difficult situations I take that route. Whereas "really difficult" situations often are the ones that do not have great impact anyways. :D So these have more training effect than real EV-impact.

"Call."