You have always countersteered... you just weren't aware of the method you were using to initiate it...
Fact is,... a bike absolutely will not turn without countersteering...
You have been initiating the countersteer, by leaning, and letting the bike fall into countersteer...
Realizing that this is happening can allow you to take more immediate action... bypassing the slow process of gravity overcoming inertia...
Turning can become much more positive, controlled, and quick...
When you lean,.. you are upsetting the balance of the bike... this (and you must think about this), will put you off the center of the tire,... and into the decreasing radius towards the edge of the tire... (imagine rolling a ball... but putting your hand slightly to the side instead of directly on top... and the ball rolls in a curve)...
This is why bikes lean into curves, and cars lean out...
As you lean.... and get onto the curve of the tire... the contact patch becomes wider on one side than the other... and this forces the fork to countersteer in the opposite direction... until the bike starts to fall left or right... (once the fall creates equilibrium... countersteer is over... and you adjust the bars to point in the direction of the turn...
The period of countersteer is almost imperceptible, unless you know to look for it... but, once you see it.... .. it is the speed at witch you can initiate a turn...
It's like being used to shooting without sights,..and suddenly having a 4x scope...
You don't really have to resist doing your natural lean... just being aware that you are leaning to initiate the counterbalance will give you more control... and eventually you will start to assist lean with your arms...
You don't have to change what you are doing... just think about what you are doing... you are countersteering with your body...
As an experiment,... (carefully)... try to lean into a turn,.. but consciously hold the bars straight,.. or even try to turn them ... to initiate the turn...You will find it impossible...
This has been tested... by welding a fork solid, and having a rider try to lean a bike to turn it... it can't turn...
... (oddly enough, a bike with fork that can only point straight or turn to the right,.. cannot turn right... I cannot even go straight, but it will go left....
...even if you don't want it to...
...
Basically,.. I'm saying, don't try to change how you ride... just try to study it... see what is actually happening...
... and you'll realize,.. you already do it...
You just have a knowledge that can give you better control of it...