There is a ton of information about what to bring for a hiking trip whether its be a short nature walk or multi-day backpacking trip. Personally I’d recommend following Mountaineering: The Freedom of the Hills, 8th Edition list of 10 systems. If you cover those ten areas with what ever equipment your comfortable using you should be good to go. The key is to know how to use them all. What good is you compass if you don’t know how to use it with your map? Or the fancy fire starter you bought that just throws pretty sparks everywhere. I mean really know how to use it, not just watch a YouTube video but go out in the back yard and light some stuff on fire 🙂 !
This is what I carry to meet the Ten Essential Systems according to Mountaineering: The Freedom of the Hills.
Navigation (map & compass): I use my Garmin the most out of the three but I practice on a regular basis with the map and compass. You could use a phone with one of the many GPS apps, even ones that can be used without a signal, however, you run the risk of killing your battery and then one of your most useful tools is now dead.
Sun protection (sunglasses & sunscreen): I put on a good amount of sunblock before I even start on the trail and use the little tube to re-apply later. During the summer months I’ll also carry my wide brim hat to block out more sun.
Insulation (extra clothing): This is what I carry for the winter months here (in addition to my jacket). In the summer I still carry my jacket with me in the mountains, because of the dramatic temperature changes that can, and often do happen. The neck thing is just a fleece tube that can be worn around the neck or as a hat/beanie.
Illumination (headlamp/flashlight): A simple LED headlamp that take a common battery like a AAA. I usually carry a back up as well.
First-aid supplies: This might seem like an odd first-aid kit, but I can make bandaids with the gauze and duct tape and the other stuff is for dealing with more serious injury. For blister control… duct tape. Again this stuff is what you are comfortable with and what you know how to use.
Fire (waterproof matches/lighter/candle): I’ve found that the REI brand storm matches are the best all around, they are like little rockets and the wood is sturdy so it doesn’t snap in half when you try to strike it. Also, the cotton ball Petroleum Jelly mix is amazing, just melt one of those tubs on low heat and drop your balls in. Once they are cooled fold them up in some foil, it acts as a nice moisture barrier later. You can also just cut a little slit in the top an pull a bit of the cotton out and use it like a candle.
Repair kit and tools: I always carry my Gerber Knife and the Leatherman stays in the top of my pack. Indispensable tools.
Nutrition (extra food): I usually have Mike & Ikes, beef jerky and GU gels. The longer the hike the more GU I bring, its the easiest and tastiest way to make sure I get all the electrolytes I need.
Hydration (extra water): Besides the bladder in the pack I have this thing with another 1.1 liters in it. Its a great thermos so it will keep things ice cold in the summer heat and keep the hot coco steaming in the winter.
Emergency shelter (tent/plastic tube tent/garbage bag): This is what I carry for my emergency shelter, it is a bit big but I use it a lot. If its cold you have the silver face in, if its hot you switch it around so it reflects the sun. I also use it for ground cover to keep my stuff from getting too filthy.
So actually, my list is 24 things I guess(if we count the food as one item), decided up into 10 systems. No matter how many things you do carry with you be sure you read up on the instruction manual, watch some videos and practice, practice, practice.