If you already know what you want overall, I suggest you create a game plan before writing any codes. For a decent full-fledged project, you could have a header screen, menu world, maps for levels, possibly with scrolling and/or smooth moving -- whatever. I usually start with whatever is first -- like the header screen. Then, move on to maybe the menu with button options for 'play', 'exit', 'credits', and 'controls'. One thing I would not do is create four separate classes for each of the option; but use one class to create the different option actors. Let the menu world retain references to them, check for clicks on them and act on those clicks. If you can, work on where 'play' leads last (the other three should be fairly straight-forward; although, you may have to adjust the controls at some point).