The English prepositions are an issue that Spanish speaking people find quite hard to have a good comand of them because there are plenty, and every preposition can be used in a huge of differente contexts and situations.
I have created this mindmap with the mostly used prepositions to show you how useful the net is. Not only it allows you to create a mindmap without any effort but also it shows you a clear scheme of the topic, in this situation the prepositions.
I would recommend you to print the document out and write several sentences where the meaning would be reflected.
Moreover, I want you to create your onw mindmap for whatever other subject you need to create mindmaps in order to make your study easier.