These are my rules for hiking take them or leave them as you like.
#5 Always pack a rain jacket and pack cover. Most of the time I am hiking in the mountains and weather can change very fast and usually the forecast isn’t so reliable, nothing is worse than being stuck out in the rain without rain jacket. Same goes for a pack cover. If you have never heard of this it’s essentially a cover for you backpack that is waterproof it usually has and adjustable elastic band and you fit it around the pack, helps to keep you goods inside your pack dry.
#4 Always wear hiking shoes. I can’t stress this enough if you are doing any kind of hiking on a trail that is not pavement hiking shoes are essential in my opinion. The tread on a running shoe is just no comparison to hiking shoes. I have seen to many friends slip and slide unnecessarily because they were wearing running shoes.
#3 If you choose to listen to music please please bring headphones. Hiking is a meditative process for me and I know for many others and listening to someone’s music is possibly the worst and can really ruin the experience.
#2 Always have emergency snacks/water. Sometimes the distance or difficulty of the trail can be inaccurate and having some emergency snacks on hand can be beneficial. Also, if you end up running into someone who is struggling and needs some electrolytes/snacks you can lend a helping hand and maybe make some new friends!
#1 This is the most important, we never talk about what we are going to eat until we start going down or are more than halfway through the hike. We came up with this rule years ago when I kept bringing up food a few minutes into a hike. Saving talking about food till close to the end gives you something to forward to once you are on the homestretch of your hike.