Sheriffs around the country would be wise to recruit and train a cadre of volunteer "Reserve Deputies" that could be activated when needed. Establish training requirements for use of force, escalation of force, marksmanship, etc.
I know a lot of Sheriffs have a "Sheriff's Auxiliary", but every one I have seen is nothing more than a donation for a sticker, or a bribe for a CCW. The Coast Guard operates a highly organized auxiliary that has thousands of volunteers that provide their own boats, equipment and time. They have contributed to thousands of rescues, searches and recovery operations.
:: Establish training requirements for use of force, escalation of force, marksmanship, etc. ::
Yep. “A well regulated militia” to coin a phrase.
And, everyday life can suffice for some of the items you mention.
Stay fit and “ready” through physical activity.
Go hunting.