How do I sacrifice in the right way?

Samael Aun Weor says that we must pay our karma with good deeds. Unfortunately, sacrifice is quite foreign to me because I have rarely practiced it in the past. I would like to help others but I do not want to do it in a superficial or unintentionally harmful way. For example, it is easy to give money to a homeless person but what will they use it for? To sustain their vices, their satiety, etc? For this reason, I find the need to contribute in a direct and meaningful way.

Perhaps instead of giving money, would it be appropriate to ask the unfortunate ones for a sort of wishlist and provide only what is truly necessary? Would this be the right approach to the third factor? Also, what about these teachings? I do not feel as though I am at the level to teach but is there still some way I can let others know about this work without letting my ego get in the way?

Thank you.