How often do you guys clean your rc cars?and how do you do so?

I recently picked up another HPI Sprint 2 Drift, Iused to have a different Sprint 2 Drift, that I had bought used, and sold maybe 2 years ago.
With both cars however I would constantly clean them after every time I would drive it, I figured it would do no harm, and could only help prevent potential problems.
Granted it is a bit of a lengthy process, regardless how often does everyone clean their car? and what do you guys use to clean with?