\3. Tarp inside the tent to protect the floor from shoes and dog toenails as well as modest amounts of water.
A tarp is a good idea! I use a large old sheet on the inside floor of my tent and put a light-weight roll-up bamboo runner over top, in the walk area, to help keep the sheet in place. Anything tracked in will normally filter through the runner's slats onto the sheet. The sheet won't keep water out; but, hopefully the plasticized bathtub-style tent bottom and plastic ground cloth will. At the end of the stay, I pick up the four corners of the sheet, pull the bundled sheet out of the tent and shake it out to get rid of any debris that may have accumulated on it. Then, when I get home, I throw the sheet in the washer and dryer and it is ready for the next trip. That keeps the tent floor reasonably clean, anyway.
4. Keep clean clothes in the car or in waterproof bags
Forgot that one! I use a water resistant duffel, which may not be good enough if a river runs through the tent.
