Monkey see monkey do is not learning.

You need develop your own strategy, learn identify maps, learn how engine works, know its limits, etc etc, just seeing what other people changed in a file will not teach you tuning. Takes months of practice and understanding, lot of hours a day.

Start by taking a target original file and identify the maps, then understand why the engine works as it does based on the maps you see, then think what you want to change in the engine behaviour and what chenges in the maps will make the result you search for, then make calculations and finally make changes in maps.

That is the way. Imho.