I am starting a big database oriented software to develop. I have full picture of the software in mind. I need to do the designing using UML. As there are various tools in UML such as usecase, class diagram, statechart, component diagram, deployment diagram, activity diagram and so on, where should I start my designing. Should it be from Usecase or from Class Diagram or from State Chart? which wich approach will help me to put my mind's picture in to design.? Please corporate with me. Thanks.