I'd recommend playing 2 types of games to get used to it.

First a single player FPS with gyro working on some kind of switch, if you have a Steam Controller, this would be when you are touching the right touchpad, otherwise with a PS5 controller for example maybe it's always on, but when you touch the touchpad it disables.

This allows you to recentre the controller when you need to so you're not twisting around in your chair.

Second play a third person action game with some kind of shooting and enable the gyro only when you pull the button to aim, usually left trigger, this will help you fine tune your aim and get used to that enhancement. I really enjoyed Horizen Zero Dawn like this and Alien: Fire team Elite.

I used to play a lot of Fallout 4 with gyro aiming on the Steam Controller, there was a lot of downtime between fights and gunplay didn't require perfect precision, which was great for learning how the controller felt. I'd find that I'd sit back with my hands on my lap, tilting the controller very slightly up and down for vertical aim and unconsciously using my foot to rotate the chair for horizontal. Once I got used to how it worked (including setting the gyro to only activate while the left trigger was held and fine-tuning the sensitivity) it became natural. My body just kind of figured it all out in the most comfortable way.

Nintendo's work is solid on the Switch. With all the gyro control, I got so used to it that whenever I'm using my Xbox controller on Steam I instinctively tilt the controller for control. Once you're used to stick for general direction and tilt for specifics it feels natural.