A horizontal line is easy to compare and alert against, but it can imply precision the auction never offered. Orders cluster across prices; candles overlap; one participant reads the wick while another responds to the close.
Begin with the origin
Find the base or swing from which price departed with visible intent. The upper and lower bounds may come from a cluster of bodies plus an extreme wick. Do not include every nearby candle merely to keep later price inside the drawing.
Make width answerable
Ask where the original reason for the zone is no longer credible. If a support area extends so far that a stop or invalidation has no relationship to the trading plan, the drawing is not helping. Narrow it using the decision timeframe or leave the chart alone.
Preserve both versions
Take a screenshot before the revisit and another after it. Comparing the untouched mark with the result prevents hindsight from turning a rough area into a perfect line. The lesson is the quality of the decision, not whether price produced a clean bounce.