I work for the state's ANS program so I'm trying to leave something beneficial on boat inspection posts even if they're a few months old.
You'll see 'clean, drain, dry' a lot - what we do is make sure your boat is clean (you'll see people feeling the sides of your boat- trying to feel any grit which could be young mussels), removing plant material if present, inspecting the motor and gimble, etc.
Drain/Dry - plugs out, wells drained, all compartments that could take on water are empty and dry (cruise with plugs out, easiest as long as you don't lose em). Lower motor to get any water out. Keep all your equipment clean and dry - example: rinse anchor before storing.
Be smart with bait, don't transport collected baits and don't bring location A's water to location B, whether inspections occur there or not. A lot of our fear is that free floating juveniles are in water, be it in a bait bucket, well, bilge, or any other compartment. We know what locations have tested positive in the past but it can take a while to find out the (bad) news, so just drain when leaving.
If you have any q's lemme know - educational materials for boaters can be found here [log in for link]
or at many inspection sites.
I feel like a lot of this is done anyway by boaters - why throw a muddy anchor on top of your life jackets, or tow an extra 200 lbs of water home with you. The more you do to keep it clean and dry the faster your inspection will be (should you go somewhere that has mandatory inspection).