Plan trips and do research so you don't miss something important to you due to lack of planning. However, it's helpful to realize upfront that you can't do it all at once, even if you spend a week or month in one place. This leaves something on the table to come back for...which isn't a bad thing.
I decided to collect coasters from restaurants/bars, brochures from National Parks, and pictures of cool manhole covers...however, I didn't get what I wanted at every site...much less see everything I wanted to. Guess I'll have to go back. Enjoy your time. Don't stress about it if you can't get to something. Log what you did this time and come back to do something different next time.
Universal Travel Tips
Pack light. If it doesn't go in a backpack, you probably don't need it...regardless if you are staying stateside or heading abroad. Assume you'll never see the people in the town you're in again, assuming they notice you at all, so who cares if you wear the same outfit twice or didn't straight iron your hair.
Travel size toothpaste and deodorant will last at least two weeks. Leave the big stuff at home and leave more room for souvenirs in your luggage.
Overseas Travel Ideology
Top Tips:
1) Pack light!
2) Pack light!
3) Pack light!
I know...easier said than done. Here's why / how I do it...
Why: Dragging a roller bag through the cobblestone streets of Italy, France, or other wonderful sites is the last thing I want to do. Also, I checked bags on a trip to England and France several years ago...they were lost in London for over four weeks. To prevent this pack light and take your luggage into the cabin with you. Also, I can think of more exciting things to do than watch suitcases on a merry-go-round.
How: Pack lightweight, breathable, water-repellent clothes. This reduces weight for the airline baggage limits, makes it easier to wash clothes while on travel, and makes them comfortable to wear.
Do laundry along the way so you don't need as many clothes. I'll book an Airbnb with laundry facilities every five or six days or search the area I'll be in for a public laundromat.
Pro Tip: If you want to book an Airbnb, contact the host first to confirm the laundry facilities are operational. I've booked accommodations in the past where a washing machine was listed as an amenity, only to arrive to find it's been broken.
Logistics seem more intimidating overseas...maybe a new language, a train system that actually functions well for cross country travel, and foreign currency. You've made it this far in life...trust me, the rewards of expanding your perspective to include other countries is worth it! Do a little research before you go and don't be afraid to ask questions when you get there.
Download Google Translate and download the language(s) you need if you don't speak it. You can translate voice, text, and photos. This can help with asking for directions, looking up words, and translating restaurant menus.
Also, download Google Maps and download the map for the area(s) you'll be in. Even if you have a data plan, it's good to have a backup incase you run out of bits or don't have signal in a particular area.
Domestic Travel Ideology
It's generally easy to get somewhere new in the US...take a bus down the coast, catch a last minute fare to a new town, or drive across the state line to a new destination. There is much to learn from your fellow citizen.
If you live in the north or south, Canada and Mexico have some great destinations that are easy to get to as well. Don't overlook the places near where you live now that you haven't been because you can 'go anytime'...but never have.
You're local, so pack light. If you forget something, it's easy to get a replacement for most things. Make sure you pack the prescription meds and things that are more difficult to replace.
National Parks: If you plan to see more than one or two National Park Service sites in a year, look at getting an annual pass. Admissions at select parks can add up quick. If you qualify for a free or discount pass (veterans, seniors, 4th graders), it might be even more enticing to visit the parks.
Presidential Libraries: If you plan to visit more than one presidential library in a year. Look at getting a membership / pass at the first one you visit. The Nation Archives and Records Administration (NARA) funded libraries have free entry for members of other libraries.
Road Warriors
Nav:
Calling all digital nomads, retirees, and people otherwise free to move about the country!
Stop at visitor centers as you cross the border of a state. Grab brochures and magazines to help you make the most of your time. Also, talk to the staff (if they're there)...they know what local weather is like and key highlights to look for that may not be in the literature.
Rest areas will become a welcome and somewhat dreaded sight. Have a roll of toilet paper, some hand sanitizer, and some baby/Lysol wipes with you...just in case.
Don't chance it with parking meters. Pay up. You don't want to try to find what tow yard your car went to in your home town, much less a different one. Also, you have a lot more gear and fewer friends to call for a ride when you're an out-of-towner.
Pillowcases make good travel companions. They can be used to wrap souvenirs (though gift shops may do this for you), be used as beach towels, or dirty laundry bags.
Nosh:
Those of you with camper vans / RVs already have an advantage on the accommodations since you're carrying your kitchen with you.
Grocery stores are your friend. Carry snacks that travel well like fruit cups, trail mix, jerky sticks, and cookies so you have options other than gas station food for a light bite. You're going to work up an appetite as you hike, bike, kayak, etc through new adventures. Have some snacks at the ready for when hypoglycemia strikes.
Have some ramen or canned tuna or other shelf stable food that can get you through a meal or two. Maybe you decided to drive late into the night and restaurants are closed when you pull into town...or the small town you pull into doesn't have anything that interests you.
Also, many hotels don't offer a great breakfast...and if they do offer more than the shameful American continental breakfast, maybe you don't feel like eggs and pancakes for eight days straight.
Nip:
I used to travel exclusively with a water filtration pitcher instead of paying for high priced bottled water or stopping for gallon jugs every day. However, there are a few cities where the water still tasted awful so I keep a gallon or two in the car for those cases. I use the pitcher to filter tap water from hotel and camp sites. Refill all your water bottles before you depart on your next voyage, including the one gallon/empty growler/whatever you got jug in the car!
Liquor laws are left to the states to decide, beyond the federally mandated drinking age of 21. An easy web search will tell you where beer, wine, and liquor are available in the state you are traveling. Some states allow beer, wine, and liquor to be purchased at convenience and grocery stores. Others limit liquor (and even wine) to state run liquor stores.