Drink plenty of water. This way you remain hydrated. It also forces you to get up a few times on long flights to get that blood circulating.
Select credit cards that give you travel perks such as travel insurance, no fees for money conversion or that may partner with hotels, airline or rental car companies.
Wear compression socks on long flights.
Ask for upgrades at the counter whether it be airlines or hotels.
When traveling by plane, train, or bus always make sure you disinfect your area with wipes. You never know who’s feet was on your tray table prior to your arrival.
Fully understand the laws and culture of where you are traveling especially surrounding gender/sexual orientation, alcohol, religion, and wardrobe.
When searching for flights be flexible. Search multiple airports that are within driving distance and see what makes sense financially. It may be cheaper to fly out of DCA than BWI for some trips.
Set up a travel account and put money in it every month.
Travel in groups to share cost on lodging, group meals and tours.