To me, "to" implies a straight line of movement, an action that moves from a source to an destination. I went to the store. I talked to her. The temperature dropped to 30 degrees. He fell to his food. It sounds ridiculous to me (the idea goes to you, and sounds ridiculous). "For" is more like a gift, intent, or focus of attention. I am looking for him (you are looking all over the place, not just a single line of attention). This is for Janet (a gift and an intent). It is too late for breakfast (no line of action). I have a question for you (intent: you, not somebody else). **Here's another example, by way of comparison. I have a question for you - intent, a gift (the question) But... You could also say: Let me put a question to you. In that case, the focus of the sentence is on the act of asking the question (the verb "put," and the direction of that action). In that case, the direction of the question is a straight line, from the questioner to the questioned. I hope that helps. I think you will just have to practice to get a feel for the differences.