This is all from my own personal experience, I am unsure if this will work for all people.
Since VALORANT has come out, I've been practicing with gridshot on aimlabs, though it has increased my overall skill I noticed a drastic increase in one area I wasn't expecting, my 'unconcentrated aim', I've played the game to the point where I got bored with it and don't perform as consistently as I used to, though, recently I started to pick up my gameplay as I found an interest in the game once again, and I would like to share this method.
Unconcentrated aim (what I am using to explain this) is how you perform when you aren't in your 'element', this means you are performing badly, none of your shots are connecting and you might be starting to tilt, I hear a lot about people complaining that they were performing like a god one game, though the next game it feels as if they completely lost their edge, this is often because their mind is distracted by something that happened recently or something happening currently, such as a tilting teammate/enemy or even a conversation you had with somebody prior, or you just started performing badly for a few rounds and lost your aim confidence, this short guide will tell you how to train your brain to perform well passively, allowing your confidence to stay at a reasonable level.
You're going to need aim labs and a show, podcast or YouTube video to watch/listen to.
Now that you have this all setup, go into aim lab and start practicing gridshot with whatever you chose to put on, you will need to focus on what is happening in the video/podcast rather than the aim trainer, this will absolutely work more efficiently with something you've seen before, your vision may feel slightly blurred/unfocused while paying more attention to the show at times but this is good if you can keep hitting shots, for example, sometimes when you spot an enemy from somewhere you weren't paying attention, your eyes may become unfocused as your mind panics shifting your center of attention to your hand movement rather than focusing on looking at the enemy first, this will directly combat moments like these. if you are using a second monitor you shouldn't actually look at the show though for the best results watch it with your peripherals, do this until you feel at least semi-comfortable with your aim, this can take some time but you're not going to be hopping into ranked right away.
As we've been told time and time again, practice deathmatch with sound off until your arms fall off, use the same method of concentrating more on the show while playing deathmatch, this way you will be directly translating your aim labs skills to VALORANT, the ideal ratio being 2 aim labs to 1 deathmatch, you should take breaks in between for a spike rush or unrated and play as you normally would, you want to keep the idea in your mind that you don't have to use unconcentrated aim when playing a normal game.
This won't solve all your problems, it will help you when caught off guard, as well as keep a good level of aiming confidence, don't forget tracking is a very important part of aiming, so practice this as well. (you don't need to do the method with tracking though you can.)