Valorant is my first competitive FPS and I've been struggling a lot with this. I started playing in July 2022 until now, somewhat consistently. These are the things I've done so far:

1) Aimlabs: This has helped me have better mouse control and mouse movement, which sharpens my active aim. Unfortunately, being good in aimlabs doesn't translate to hitting headshots in valorant as valorant is a quite different than aimlabs. No doubt that this has helped my aim but I don't think it can help me much more at this point.
2) The Range: The range has helped me hit headshots and it is in some cases better than aimlabs in my opinion. This is where I've sharpened my movement (bursting, deadzoning and air strafing) along with my raw aim (flicking, tracking). Since the bots don't shoot back I have time to make sure my crosshair is aligned with someone's head and not slightly off. All of the above has helped me a lot in lower ranks.
3) Deathmatch: The elephant in the room. Deathmatch has a lot of pros but also a lot of cons. Deathmatch is great for practicing your crosshair placement. It is also great for practicing movement, however this heavily depends on which map you're playing and which players you're facing. I often find myself having a better time practicing movements when the fights are long range than short range, even if I am fighting multiple people simultaneously. If it's a short range fights it depends on whether the enemy wants to hit your head or just wants you dead. This is a big issue in dm which I don't think can be fixed. People simply don't take their time to hit your head in short-medium range fights, which translates in bad first shot accuracy. Deathmatch is great for warming up my mechanics but it can only train them to a certain extent, if I want to get my mechanics to a radiant-level player, do I really have to play 1000+ hours of ranked?
4) Competitive: Last but not least: competitive games. I have no idea how to practice in an actual competitive game as I want to win the game and not only hit headshots. When I consciously think about making sure my crosshair is on someone's head, I can't simultaneously think about the game. Which then results in me often whiffing my first shots.

Making sure my crosshair is on someone's head is not subconscious to me yet, and I have no idea how to transition it from conscious to subconscious. Does anyone have an idea on how to change this? I know that by playing more competitive games I will eventually improve but is there absolutely no better way of doing this than playing thousands of hours?