The pen idea is very good.And if think that everything is cleared on paper look at it and decide if it`s a bit complicated for you.
If it is then you try to write it step by step.
You make the menus first, in separate project make game mechanics if they are too complicated and so on.Try to make them plug`n`play so you do not need to rewrite or do rewrite much less code to assemble the game from separate bits of code.
I`m making 3D clone of 2D game now and i begin writing with game mechanics first, one by one.Some of them was painfull.Then i write score table with highscore and everything(btw you can search code snippets for "highscore"), i need to make menus then their options.After this i assemble everything and stable it if there are any bugs.
Where there is a will, there is a way.
I often edit my posts, that`s who i am
