Great question — answering as the UphillTech team:
This is how I go about it, I might be wrong, weird and non-conventional than what you follow, but this is what I have learnt over the years, and I see a lot of hikers (that are certainly better than me) do. Eyeball it -- Pick the one that appears more frequented than the other. If a trail appears to be slightly better, then its better to follow it and improvise on it later if required. See if it follows the contour you want to be at -- I typically avoid going up or down the trail unnecessarily if I know that the contour where I am, and where I want to go is easily connectable, the people who engineered these trails decades ago are far better than us in understanding the contour and...
Full answer by WedaPashi: https://outdoors.stackexchange.com/a/30439 (CC BY-SA 4.0).
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