Reduce the number of open problems
A solo player handles threat, navigation, inventory, and extraction alone. Do not add a new layer, unfamiliar Vessel, and high-value carry goal in the same test.
Choose one unknown and keep the rest of the run familiar. That makes a failure informative instead of merely expensive.

Preserve movement and awareness
Avoid filling every slot with the first recoverable object. Keep enough capacity and visibility to react to a threat or a better find.
Use doorways, sightlines, and known return markers to prevent a fight from cutting off the only safe direction.
Treat a small extraction as progress
A short solo return can fund Outpost growth and reveal a stable rule. Repeating that route with one new variable is more useful than chasing a dramatic deep run every time.
Community solo advice is a starting point; check every tactic against the current patch and your own Vessel.

Sources
Official GRAIN ROT Steam store page →