Methodology for BGP policy development

I'm looking for some good material on the methodology (best
practices) of moderately-complex BGP policy development.

I've found no shortage of the tools (prefix lists, community
list filters, route maps, etc) for *implementation* of BGP
policy. Including plenty of router configuration examples.

I'm looking for help with the steps before the router

What is a good methodology to go from a set of (~30-50)
narrative descriptions ("Propagate prefixes received from
Customer Type X only to Peers Type Y") into a optimal,
comprehensive set of community definitions,
prefix/community/ASpath filters, route maps, peer templates,
policy statements, etc?

What methodology works for you? Are there
presentations/papers/books/discussion threads that cover
this aspect of routing policy development that you would

Thanks for your help.