I have just finished developing a large bespoke content management system, and scribbling ideas down on the back of a fag packet has nearly cost me my sanity, and my job. I essentially made this up as I went along, and it all went horribly horribly wrong for a long time.
From now on I need to plan out my projects properly so my employers, the client, and I know exactly what is going on. At the moment I am working on my own, but in the future I may have to work with other developers so need to ensure everyone knows what is going on. I was thinking I could make a flow chart of the general overview of the application, then each part create a separate diagram showing how it works step by step. That way I can tick things off as I go along, and it will allow me to test it more comprehensively running several possible scenarios.
How do you plan out your bespoke software development projects? Is there any particular method, tool or language (uml?) you use?