Nothing - I haven't even really thought about it.
I have though about implementing some of these measures but have yet to do so
A Fire plan (this means you have thought about and written down the what, when, where and how)
Provision of adequate escape routes from work areas
Shed construction and fit out to suit activities( eg, separate areas for wood and metal)
Regular clean ups and removal of sawdust and flammables
Safe disposal of oily rages etc
Smoke or other suitable fire detectors
Suitably located fire extinguisher (i.e. not in a cupboard or under some stuff)
Suitably located fire blanket (i.e. not in a drawer or under some stuff)
Flammable liquids located in closable steel cupboards
Adequate ventilation of fumes and flammable gasses
Direct line to Fire Brigade
Other - please specify in a follow up post