my lot size is never fixed and will change at any time with time. my usual lot size is 0.01 to 0.05
but in special cases I use .5 or even 1 to boast my advantage at the right time.
I think for a good trade it may be necessary to keep the lot size for a certain period of time.
I'm afraid the lot size really depends on the strategy used. But be careful using lots lot size
because it is very risky. it will give big profit but also big loss.