I want to design a 2D game idea with C#/XNA. Between school, project inexperience, limited resources, and other things that may cause me to bail on the project I am going to try to plan it out before I jump in:

* What are some key aspects you've noticed in a successful personal project?
* How did you (successfully) draw revenue the project (besides asking for donations)?
(Note: this is not the main purpose of my project but would be nice!)
* How do you plan non-programming aspects like window layouts (UI), flow of game, and look and feel?
* How do you bring an abstract idea of a game and making into a real product. What tools do you use in your sketching and planning?
* With limited resources (artistic talent and money), how do I create some of the art resources I need (besides stock art)? Or should I not worry about that until I have a finished product?
* Finally, how do you break barriers in your code (may it be knowledge, time, or perseverance)?