Lining care fits in one paragraph, which is why we repeat it often.
Hand wash with warm water and mild soap. Dry with a towel right after; leaving water standing is the single worst thing you can do to any peetal piece. Store it open, air reaching the surface.
That is the routine. Everything else is avoidance: skip the dishwasher, whose detergent is harsher than anything in the sink. Skip steel wool and scouring powder, which cut soft tin quickly. Skip the urge to polish the inside; the lining is not meant to shine, only to work.
Wooden, silicone, or steel spoons all cook fine. Steel just leaves the most visible swirl marks, so pick your spoon by how much you care about looks versus scrubbing speed.
Follow those habits and the lining reaches old age gradually, evenly, with nothing dramatic along the way. Which is precisely the goal.
Soft sponge and mild soap beside a peetal vessel drying upside down on cloth.