Reach back and teach the people coming up behind you. Explaining it makes you better at it too.

Teaching forces you to find out what you genuinely understand. Half of what you know sits in your hands rather than in words, and you only find the gaps when somebody asks a question you cannot answer cleanly. The person learning gets a shortcut and you get a clearer map of your own skill.

Find one person a year or two behind you and offer to walk them through something specific. Keep it to an hour. Notice which part you struggle to explain, because that is where your understanding is thin.