I was only able to get to Onyx in SWAT a ways back due to monitoring how I play. There’s multiple things you can do to increase your capabilities.
Starting from the ground up:
1) Set up a shooting range.
Make obstacles that you have to jump and boost sideways in order to shoot, where you only have a short window to hit the object. Just keep doing that with a static object until you feel you’ve done enough for the day. Getting better at a video game isn’t like a workout. Slaving away won’t do anything but harm you. Once you’re out of your comfort zone it’s time to stop. Once you’re done with statics, switch it up with moving targets. These aren’t hard to make and you can YouTube how to do these.
Switching from mortar to rock:
2) Now if your aim isn’t the issue and it’s your skill in certain situations, then you need to practice “sparring”.
Start with pistol 1v1s in SWAT, then move to slayer after you feel you’ve gotten pretty good at hitting your shots with low damage. Once you’re hitting 80% perfects with a pistol, you’re ready for the next stage.
Becoming or attempting to become a Diamond tier player:
3) Join clans.
Joining clans is tedious and annoying but you will get better by fighting other people who are at or above your skill level. You’ll learn new fighting techniques this way and you’ll learn to also work with a team better with better call outs this way. This is when you’ll discover your actual play style.
Working for that Champion tier gameplay:
Once you’ve accomplished those few things, take it into competitive matches which will set you up with games of people at or above your skill level. In Ranked they will actually test your newly achieved level of skill. That’s really the last step. Getting good at Halo 5 before all the craziness Halo Infinite will bring is a good idea since you likely will need that skill going in.
Now let me make this clear:
You don’t NEED to be good at Halo to enjoy the game. Don’t focus on being good while you’re getting better, but rather focus on enjoying the game while getting better at the game. This will help you rage less and last through more games playing competitively. Because you’ll be able to laugh at your mistakes rather than feel every slip is a massive error.
If you can’t get good with these tips, that’s fine. There’s nothing wrong with being bad at Halo as I mentioned. Your skill level could just be at a plateau or it could just not be your day. You will experience days where you do not as good as you were before. This doesn’t mean you’re bad, but you’re clearly not in the mood to compete. Learning to identify these moments will make it easier to change your mood and be better in general.
Edit: I made a quote rather than an edit below this if a mod could delete that, it would be appreciated I didn’t mean to do that.
i wanted to add that doing you versus multiple people at once is another good way to get yourself used to challenging and horrible situations where you’re outmanned and outskilled so you have to use tactics to win.