A company can post excellent results and fall 12%, because expectations were higher still or because forward guidance softened. Price doesn't react to the numbers but to the gap between the numbers and expectations, and expectations aren't published anywhere tidy. That's why experienced traders don't try to guess the direction of a report.

First, and most common among swing traders: don't hold through earnings. Close before, and if the pattern is still there, re-enter after. Second: hold at half or a third size, accepting the gap as a bounded event. Third: only enter after the report, using the sustained drift that follows a strong surprise.

The third is especially interesting: a stock that gapped up strongly on good results and guidance tends to keep drifting the same way for weeks. Entry happens after the information is public — no gap risk — and it is one of the most documented effects in the market.

What's forbidden: discovering by accident that earnings are tomorrow. The date is checked before entry, always, as part of the checklist.