How can I make it easier?

For manual focus, the best thing is a speed reducer – a small knob on a 2-speed focuser that takes 6-10 turns to turn the big focuser knob (and focuser shaft) one turn.  With a speed reducer, the is magnified to comfortable 6°-10° rotation and the torque required to turn the focuser shaft is reduced 6-10 times.   For the fast imaging Newt (f-4), the miniscule ±0.3° becomes a perceptable ±3.0°.

Still you're turning turning the focus knob by hand so there's a good chance the telescope is still shaking and the star’s image is vibrating and blurring.  Most likely You’re still stopping every so often to let the vibrations damp out so you can check the star's focus, then turning the focus knob some more (hoping that you’ve turned it the right way and by the right amount), stopping and checking again, try to figure out if it’s better or worse, go the other way to check and so on.

And there's a mechanical drawback for speed reducers as they use ball bearings, instead of gears, which can slip under heavy load especially when the focuser tension knob is tightened to lift the load without slipping.

How can I make it even easier and more reliable?

Motorize your focuser. A motorized focuser won’t shake the telescope while your focusing, and the motor can make very small rotations of the focus knob more reliably and precisely than you can by hand. If you select a focus motor that attaches to the single speed knob, you won't have focuser slippage as with a speed reducer. But pick the right focus motor.