Settings > Edit Settings > scroll to bottom > click Controller Tuning > scroll down to Controller Left Stick and Controller Right Stick.
Adjust: Center Deadzone and Axial Deadzone, and Max Input Threshold.
Blowing compressed air into your analog sticks bases is also helpful.
There are also YouTube videos explaining all of the game settings.
Additionally, you can use Kontrolfreek analog stick caps to increase comfort and accuracy by stopping your thumbs from sliding on the analog sticks. Analog stick caps do not break any game rules.