Ask Lemmygrad

Just give them a factual historical education and teach them to think critically about how the economy and society works under capitalism. Teach them to question narratives by questioning the interests of those who propagate them. That is the first step.

Once someone has formed a solid understanding of how the world works beyond the lies told by liberal propaganda, they will eventually find their way to Marxist ideas, because only Marxism offers a coherent framework to explain what we observe.

If you are too explicitly advocating for communism to students who are still caught in an idealist understanding of the world, you might end up being accused of trying to propagandize them.

You have to remember that many of them come with pre-conceived ideas that will be heavily reinforced by their families.

So my advice would be to view yourself as laying the foundation, not as the person who will necessarily "convert" them.

(Though, if some show an interest and aptitude to learn more, you can of course guide them further along and point them toward resources they can explore on their own time.)