In order to get the application of prepositions right in learning the language, a picture image might help but so would verbal associations. In that case the person learns to use a certain prepositions where there is a certain kind of word. A word suggesting movement will likely need to. Since speech or talking requires the movement of words from one person to the next, the preposition to use is to. So we talk to people and speak to them. Lately I have heard that someone is "speaking with somebody" and consider that grammatically incorrect although it is tolerable when dealing with populations that insist it is a correct form of speech. Many may use it because it has become popular over the past thirty years and is probably just as well diffused in language texts but if I talk to someone I won't be talking at the same time as the other person unless I don't want to hear the other speaker or have him hear me properly.
Similarly to is used before an infinitive or a verb that has not been conjugated in a sentence, especially when following a gerund or another verb that has been conjugated. It is associated with words like go, come, arrive, walk and run which all require displacement.
The preposition "in" is used to refer to something that is within the confines of a space. That space may be closed as in a drawer, or partially closed, as in a hand. Confusion occurs between "in" and "into, when the speaker wants to refer to something in a room. Into is clearly demonstrated by having the teacher go into the closed space from outside and so can be associated with the transition from one location to another. "In' would then be associated once the person has moved into the room and is now "in" an enclosed space.
