Take only pictures, leave only footprints
The phrase "Leave No Trace" can mean a lot of things to a lot of people. The concept that is self-evident is that the natural landscape must not be altered in any way. This changes how we view the outdoors, and how we prepare to spend time in nature. There are groups dedicated to provide education on this topic, here are some tips to help you leave no trace. Take only photos, and leave only footprints.
"I think I cannot preserve my health and spirits unless I spend four hours a day at least—and it is commonly more than that—sauntering through the woods and fields absolutely free from all worldy engagements."
-Henry David Thoreau
Pack a snack
If you are familiar with the outdoors and spending long periods wandering, it is good to pack some food. The world is your oyster, just remember that you have to carry it, so light options are a favorite of most. Hikers like small snacks that they can eat while moving, often with sugar for quick energy. Day hikers like sandwiches, which are easily stored and carried in their pack. My kids like goldfish for one of their trail snack options. No matter the choice, you have to bring out what you bring in. If you have to pull a tab or open a lid to get to your food, make sure the removable portion stays with you. Bringing a sealable bag is a good choice, so all waste can be folded small and kept together in the bag. When a trash can is available, it can all be disposed at once.
Re-Usable Hydration
I cannot stress this one enough. Hydrate-Hydrate-Hydrate-Hydrate-Hydrate-Hydrate! You have to know yourself for this one. How much water you bring is determined by distance, temperature, heat index, pack weight, elevation gain, and so on. So you have to know yourself, and see how your body acts. As you get into hiking, make special note of how much water you bring and how far you travel. Personally, I either bring a 32 oz. bottle or a 3 liter reservoir, no in-between. Dehydration can hit you when you least expect it, so do not let it. I do not mind carrying the extra water, it may not always be for me, but it will never be in a disposable container. I once climbed a mountain with a friend who brought two bottles of a name brand water, one for up, one for down. At the summit, he dropped his "down water", we watched as it shot down the steep cliff face beyond reach. Needless to say, we could not recover the bottle, and the trip got shortened.
Proper Footwear
This one seems like it is self-explanatory, but it is not always the case. Hiking footwear is very different from work boots or running shoes. There are often thicker, more rigid soles to keep your foot from twisting. Heavier grip for wet rocks and mud, or designed to become one with your foot. When it comes to hiking, compromise somewhere else. Go to a reputable seller, try them on, see how they fit you, and get a quality pair. You can thank me later for this one. Why does this fall under "Leave no trace" you may ask. Well, if a rescue team has to come get you, the "Leave No Trace" concept is out the window, just because someone didn't want to get the right shoes.
These are some of the ways you can leave no trace, that may not have been immediately obvious. Beyond these, there are seven principles to Leave No Trace
1) Prepare and plan ahead. Know what to bring, and how to bring it back.
2) Camp on durable surfaces. Camp sites are not made, they are found.
3) Dispose of waste properly. This means all waste, even your own.
4) Leave what you find. This can be a tough one.
5) Minimize campfire impacts. Know local regulations.
6) Respect Wildlife. You are in their home.
7) Be considerate of others. Think of the children.