I've recently learned that snake-proof boots exist. I haven't bought any yet because I can't go and try them on, but they seem like an excellent idea. I've done some research into them, and I've read that they do actually work quite well- snakes can't bite too terribly hard, so can't pierce the material. There's also a sort of shin guard device you can use, that straps onto your lower legs and can work with many types of footwear. Both are meant to protect the legs from snake bites, as most snake bites that don't occur from handling the snake, happen when someone treads on one.
Depending on where you live, this may or may not be needed. I live in Texas, which means snake protection is generally a good idea. We have many snakes, including multiple venomous species. I don't intend to step on any intentionally, and I do my best to watch my step when exploring, but the boots seem like a good precaution just in case. They're effective against thorns as well, which is nice, and will probably come in use frequently.
You may like to look into a pair of hip waders. Aside from the obvious benefit of being able to walk in water without getting cold and wet, they provide some protection against my least favorite spiders to encounter: fishing spiders. Fishing spiders are a lovely group of spiders that can actually run across the surface of the water, and use it to catch small fish. If you happen to be wading near them, they may decide to run up your leg. I have nothing against spiders as a group, but I don't remotely like to have them suddenly run up my leg. So even when the water isn't too cold to walk in comfortably, I like to be able to at least keep them from running up my bare leg and potentially getting under my clothing.
Hip waders are nice to have. Not only for the birds, either. If you walk slowly and gently, and stand still in the right spots, fish will often come near you once they've settled from being disturbed. They're mostly afraid of shadows, not of wader-clad legs. I say this because I tend to assume that people who are interested in birds may also be interested in other wildlife.
They would probably also provide some tick protection, silly as it would look to stand in brush with hip waders on.
Be aware that wet clothing can sap heat away from your body at an alarming rate. If you get yourself soaking wet, in temperatures that are any lower than maybe 60 degrees F, you should go and get dry. Hypothermia can occur at surprisingly high temperatures if you're covered in soaking fabric. It may not happen in every case, with every person, at those relatively high temperatures, but is still a risk. If the weather is freezing, enough soaked clothing becomes a "go to a heated place immediately" sort of emergency.
If you ever feel cold enough to shiver, and then stop shivering without having gone and gotten warmer, you have probably gotten some degree of hypothermia. If that ever happens, IMMEDIATELY go and get warm, before it gets worse. The same goes for if you feel confused with no evident cause, and for several other things. I doubt you'll get hypothermia if you dress appropriately, but if you plan to go and be outdoors for long periods in cold weather (though I don't know how cold your local weather usually gets), you should read up on its symptoms. Both for you, and for others you might happen to encounter.
Also, read up on what snakes you have in the area. Learn what venomous ones look like. If you ever see a snake and aren't certain that it's nonvenomous, it's best to treat it as though it is venomous. Which is to say, give it a wide berth.
Snakes don't attack people. They bite if you get close and stress them out, and some species will lunge towards you in an effort to make you think they're dangerous. I believe there may be a couple of particularly aggressive species in Africa that will close a gap between you and them on purpose, but that's very rare. Snakes don't want to fight you, they want to get away from you uneaten. Venomous ones don't want to waste their venom if they can avoid it.
Find out if you have ticks locally. Some can carry some really nasty diseases. We have a lovely species in Texas whose bite grants a serious, potentially deadly allergy to red meat! Fascinating, but not fun.
In general, learn if you have any dangerous wildlife, and what to do if you happen to find any of it.
If you decide to go out into a fairly wild area, where you could expect to encounter few if any people, it's good practice to tell someone where you've gone and how long you intend to be there. That way, if you have an accident of some sort and don't come back, they'll know to call someone to go and look for you. Very unlikely to happen, but it can. That's mostly important if you'll be in an area with no cell service, of course- if you're in an area you can easily call 911 (or your local equivalent) from, you should be fine.
You can get a battery backup for your phone. You charge it at home, then you can plug your phone into it to get more power. Useful in general, but especially if you're going off on your own to somewhere people won't hear you if you shout. You're very unlikely to be injured in a way where you'll need help to get out, of course, but it's still good to have something you can do just in case. Especially since twisting your ankle is relatively easy to do, and would put you in a position to need help.
(I'm aware most of this is advice, rather than clothing suggestions, but I hope it's still useful.)
