Basic exercises:

alliteration/alphabet - pick a letter and construct a freestyle using as many words beginning with that letter or letter sound as you can, while still being coherent

see-and-rhyme: the obvious. rhyme about everything you see around you. add levels of difficulty by trying to string them together into a narrative, turning objects into metaphors (e.g. a ruler can be described as a monarch, etc)

stream of consciousness - follow an idea to its absolute most absurd conclusion (the ruler, above, being a monarch, but really a monarch butterfly, ruling over an empire of caterpillars, which are actually Caterpillar tractors, which are part of an agricultural multinational corporation trying to take over global food production...or something like that)

Narrative - spontaneously creating stories and trying to add layers of depth as you go is a great skill-building tool. to add difficulty, tell the story out of temporal sequence and try to hold elements of the story in memory and return back to those hanging tangents, while maintaining a steady rhythm

all of these exercises should be done over the most challenging rhythmic patterns available. classical or free jazz are good standbys. stick to the rhythmic pattern as long as long as possible and keep pauses as short as possible. film yourself and review your performance.

rhyme everywhere.

that is all.

edit: I want to freestyle in Brisbane one day. If there are promoters paying people to freestyle over there, I will make it to that part of the world somehow.

Peace,

Spirit (Alan)
http://wutangbook.com