I used to main soldier when I started playing TF2 (now I go back and forth between Spy and Medic). Something to always keep in mind is your health when you’re rocket jumping. Rockets do a significant amount of self damage and even if you’re using the rocket jumper, even fall damage will add up and every time you encounter an enemy after a rocket jump, you will most likely be at a lower than ideal health. Playing soldier is a balancing act between using rockets to move around while also using them in battle (usually), so you also need to pay attention to how many rockets you are using so you are never caught in an awkward situation where you really need it.

It helps to get into character. Try giving speeches over voice

Jump academy is a great resource for learning the basic rocket jumping mechanics, but in many cases it will not teach you the best way to move around “actual” maps. The only way to learn this is to continue to play soldier. running gunboats + escape plan will make this easier to learn quickly in my experience. I have close to 900h on soldier as well as a few seasons of 6s experience, so the other tips I give will be mostly for a gunboats “roamer” playstyle.

You might have heard that an important skill to learn on the scout class is to learn when to pick your fights and learn when to back off and live to fight another day. This is even more true on soldier once you have become a proficient rocket jumper. You really only want to take fights if you have the drop on people or if you are positioned better. Map knowledge is imporant for this since you want to play around high ground and health packs whenever you can. You will learn this will time, but if you want to speed up the process you can probably find streams/videos of better players using these spots - abuse high ground as often as you can.

Crosshair placement is relevant on soldier - if you are turning a corner, don’t aim at head/chest level, pre aim at the ground so if there is someone there you can direct his feet to juggle him or at least hit him with a splash rocket. This is difficult to explain only via text, but hopefully that makes sense.

Knowledge of where health/ammo is is incredibly important for soldier since he is pretty reliant on these to do well. If you are playing an unfamiliar map take note of where everything is. Rocket jumping to a health pack is almost always worth it if you don’t take fall damage. You lose 12-20ish hp to gain at least 40. Once you have hundreds of hours on “roaming” soldier you will develop really good internal timing of when a health pack you took will respawn. When you reach this point you will get really really good at playing around health packs.

Ammo management is really really important on soldier. In a fight I always try to have at least one rocket loaded so I can jump away if I am losing. Of course this isn’t always possible, but the point here is that you should pay attention to how you are using your rockets. It is often not worth it to go for extremely difficult airshots or random spam across the map.

Regarding your original post, if you find yourself dying extremely quickly you are likely out of position. Playing against good soldiers can feel like they are just jumping at you every time they see you and getting the kill, but that is usually not the case

make sure you’re following the Soldier Basics:

1. get high ground
2. shoot at feet (Guaranteed Splash Damage)

the best soldiers (or any good players really) will surf enemy damage onto high ground and then be able to shoot their whole clip at the enemy instead of rocket jumping.

but I mean the simple answer is to play him more. More jump maps could be good. If you’re jumping a lot make sure you’re using gunboats. Also highly recommend turning on autoreload; getting that extra rocket loaded while airborne without having to scramble for your r key can make all the difference.

could probably try grinding mge with some friends

Tbh without watching you play, it’s hard to say. I’ve always found success in raising my skill level by jumping headfirst into ranked and paying SUPER close attention to the (in this case) soldiers around me to see better behaviors and displays of heightened game sense.