Some notes on self-training

Taken from an Army/GWOT vet:

There's a lot more to the equation than marksmanship, but definitely continue your range training.

Practice quickly engaging multiple targets. In the Army, we qualify on lanes with human-sized targets that pop up randomly from berms at 50 to 300M. Targets are only up for a few seconds, so you have to scan your lane, quickly acquire sights, and accurately engage. This is hard to replicate on a regular civilian range, but you can build similar skills with either multiple paper targets at different distances (if your range lets you have more than one per lane), or a single target with multiple bullseyes. The bullseyes should be different sizes to represent the enemy at different distances. Have your battle buddy call out your targets in random order, and enforce a time limit. "Closest" targets should only get ~3 seconds; "farthest" get a little more time.

Practice engaging targets from as many positions as possible (prone, standing, kneeling, supported, unsupported, from low ready, from high port, from behind cover, on both sides, etc.). Practice with optics (if you have them) and just iron sights. (You should have both; "two is one and one is none.") Practice with an elevated heart rate (even at a public range, you can do pushups or jumping jacks to get your heart rate up when the line isn't hot). Practice with and without body armor or whatever other gear you have. Practice under stress, with your buddy screaming the countdown in your ear.

There is also a dry-fire "penny" drill you can practice at home for better trigger and breath control. Plenty of videos online.

But arguably more important than marksmanship alone is your team's ability to shoot, move and communicate effectively, even if it is just you and a buddy.

Read Army FM 7-8 (easy to find online) to understand basic infantry battle drills. These drills do not require live fire, or even for you to be carrying—what you're practicing is how to move as a team in different scenarios on instinct. There is very, very little on buddy teams (2 Soldiers) and fire teams (4+)—Army doctrine mostly focuses on squad (12+) and larger elements—so unless you have a lot of like-minded friends, you'll have to adapt. For example, most squad-level drills divide the squad into Alpha and Bravo fire teams. You can scale those down to two-man drills. Use common sense in deciding which drills are relevant, as some of this stuff is designed for conventional warfare.

If you're in an area with open land where you can do so safely, also practice firing from a vehicle. Both sides.

Everyone's first instinct is to focus on rifles, but it's just as likely, if not more so, that you will be in an environment where you need to carry concealed, so practice with handguns, too.

There are competitive shooting groups like IDPA that do similar handgun drills, but I don't really recommend them. Some of their rules are designed to minimize liability and build what I would consider bad habits in a real scenario.

Practice two-man buddy rushes. You don't need to be carrying for this, but it helps to use the buttstock of a rifle to absorb some of the shock of dropping into the prone. Plenty of videos of this around. If you have a third person, place them at the end of a lane with a mix of cover and open areas, hand them an airsoft/paintball gun, and practice bounding towards them while avoiding getting hit. (Wear safety gear as necessary.)

Practice room clearing. You don't need live fire to practice movement. Lots of videos on this.

Read the Soldier's Manual of Common Tasks. These are the foundational skills you learn in basic training—first aid, land navigation, etc. Some sections won't apply, but the following are critical skills:

I cannot stress this enough: Practice basic first aid—CPR, how to apply a tourniquet, how to treat chest wounds, etc. Get a matching IFAK for everyone on your team. Ensure that everyone's kit is in the same place on your person—not in your ruck. If you ever need it, you don't want to dig for it, and that's doubly true if you lose yours and need to use your buddy's. Priority items are: tourniquets, gauze, pressure dressings, clotting agents. Practice improvising these items, too.

Practice land navigation with a compass and a paper map (don't assume you will have a functioning cell or GPS if things get to the point where all of this matters). You don't need weapons or gear for this other than a decent civilian compass. Just get out in the woods. Practice in urban areas too (if you can under present circumstances). Learn the topography of your area inside and out, and identify likely avenues of enemy approach, sensitive infrastructure, where the land forms natural choke points, etc. Add paper maps in ziplocs to your kit.

That should keep you busy for a while. There is no shortage of tacticool content floating around, but you need to learn these fundamentals before any of that will make a difference.

Edit: Also, get in shape and get acclimated to wearing your gear. Focus on bodyweight/HIIT exercises (burpees, pullups, pushups, etc.), running, and possibly swimming as well if you're in that kind of environment. If you have a bug-out bag, body armor, etc., wear it whenever you can so your body is already used to it when you actually need it.