What is the ethical issue? (If you can’t recognize an ethical issue, you can’t decide how best to act.) And once you recognize it: could my decision be damaging to someone else? How damaging?
What’s at stake? (Identify who has a stake in your decision and whose concerns are most important.)
Evaluate the options for acting. (If I act in X or Y way, will I be producing the most good and least harm? -- utilitarianism Will I be acting as the sort of person I want to be? – virtue ethics. Will I be acting the way I’d expect others to act in such a situation? – duty ethics. Etc.)
Make a decision and test it if possible. (If it’s not an immediate situation, test your decision on someone who’s opinion you respect.)
Act on your decision and reflect on the outcome. (How did your decision turn out; what have you learned from the situation?)