Roll a spare pair of socks and underwear inside a clean tshirt and store them at the bottom of your carry-on bag. It won’t take up much space, and it’s a lifesaver if your luggage is lost or delayed and you need to freshen up.
Domestic airlines will not pay you for cash, electronics, jewelry, art or antiques lost, damaged, or stolen from your checked luggage. Put these things, and anything else of “irreplaceable value” in your carry-on bag instead.
Airlines’ liability for your lost checked bag is $3300 on domestic flights, $1131 on international. Your carry on luggage is the safest place for anything more valuable than that. Most carriers exclude claims for cameras, art, electronics and jewelry from this coverage also.
Not sure how to handle the dirty clothes you accumulate during your trip? Most luggage has a zippered interior liner (intended to allow access to the handles or wheel components in case they need repair). Store laundry underneath that liner to separate them it your clean clothes.