What is the prescribed Kaffarah for falsely saying 'wAllah' to something? And how should I proceed if I am unsure of the number of times I have done it?
Bismillah
In Surah Baqara verse no. 225 we read:
So as it is apparent from your question, you have no real intention of swearing by God's name and it's just on your tongue, so there's no need to pay Kaffarah for that.
Of course it is better to try hard to quit this habit