I've taken many, many trips in a long and vigorous career. A few of these stand out, and I've spent a little time thinking about what made them work.
1. The best trips have had a few specific goals, and plenty of flexibility about how to reach them or to change them if need be. In 1962 I spent the summer in France at the age of 16. I bought a used moped, got a Michelin Red Guide, and formed the general plan of touring counter-clockwise and getting as far as I could. I definitely wanted to see Chartres, Nice, Monaco, and the French Alps.
This plan actually worked! (Except for perpetual moped breakdowns and getting thrown in the slammer in Marseille, for improper documentation for said moped. But that's another story). It gave me a few definite targets and plenty of opportunity to go see what was interesting. And at that age, everything was interesting; I knew virtually nothing except how to open a wine bottle and how to speak pretty good French.
Similarly, a couple of summers ago, I headed West with my camera gear and my dog. I wanted to see the Badlands, and that was about all I had in mind. I added destinations / and sights to see based on what I learned from local people. This worked great! For instance, from the lady who ran the Rocket Motel in Custer, ND, I learned about an upcoming old car event in Deadwood --- got great shots and won $400 the casino (enough to pay my dog's vet bill, but that's another story)
2. Talk to people. I'm a dyed-in-the-wool introvert, but I have a secret weapon: my wonderful dog Ginger. She loves people, and they love her. She can open doors to people's hearts faster than the IRS can get to your wallet. I would talk a bit, then say "what's a place that's special for you, that I might want to see. Doesn't have to be fancy or spectacular, just someplace a little special." This simple question led me (and Ginger) to this Tongue River trail and some great pictures.
3. Get off your asphalt! There is virtually nothing worth seeing from an interstate, and very little from a serious stretch of blacktop. But dirt roads! Ah! They offer interesting scenery, great chance encounters, and a sense of surprise around every bend. Because they slow you down, they force you to pay a different sort of attention .... and you can readily park and hike back to that interesting bit of rock or unexpected sweep of wildflowers.
4. Sleep simple. I like to alternate 2 nights of camping to 1 night of cheap motel. This really contains costs, gives you more people who know what's going on in the vicinity, and still provides at least some small measure of hygiene. I use a tent, air mattress, sleeping bag, and minimal cooking gear -- and that's about it. Don't carry the stuff on my back if I can help it, because I'm already schlepping camera gear --- and it's heavy! So it's car-camping for me.
5. Speaking of camera gear, I use two cameras, a medium-format camera with a huge digital back for landscape work, and a Nikon D-700 for quick work. Combined this stuff gets heavy. You can pare it down somewhat by eliminating lenses you don't think you'll need that day, but it still weighs a bunch. My personal kit contains the Nikon and Mamiya, 2 lenses for each, and filters, batteries, cf cards, etc. The Nikon is fast enough that I can save some weight by using slower glass. If I'm taking the Mamiya, a tripod is essential. Carbon fibre is worth the cost for weight savings.
6. I also carry a compass, a GPS, a water bottle, a bit of rope, and a small first aid kit. A folding brush saw goes along if I'm expecting waterfalls. If I'm with a pal, I take a pair of dirt-cheap walkie-talkies. At age 64, I think it's a great idea to be able to yell for help.
Speaking of GPS, it may sometimes say a road goes through when it doesn't. This happened repeatedly in the Western states, and even in New England. GPS works great for getting you unlost. But don't give up really good paper maps and state atlases.
7. Don't over crowd your agenda. I'm prone to this, and it is a bad idea. 7 cities in 5 days is a lousy way to experience, savor, sample, photograph, and remember ANYTHING. So keep your program very simple, and be open to whatever comes along.
8. Do get all the background info you can on the place you're going. This helps you make choices, set priorities, get good prices on accommodations and food, and let's you know a little about what to expect.
9. Learn how to make lemonade. On my recent photo safari to Washington state, I had two specific objectives. Weather and circumstances interfered with achieving either one. For instance, we spent a morning when we had planned to be on the water waiting out fog and repairing the boat motor. (See the rant below about the Makah Indians). But I used the opportunity to shoot bald eagle pix and to take a couple of really nice boat-in-the-fog images.
10. I love my Subaru. It doesn't get stuck, and will get you pretty near anywhere if you take it very slowly when off-road. Decent mileage (not great), and room for gear and dog. I'm finding that photo trips by air are getting way too costly, largely due to luggage surcharges. So get off your asphalt and have a great time!