How to study masters games - my humble "adult improver" 2 cents

I'm going thru "First book of Morphy" by Frisco del Rosario. My progress is very slow, and the problem is I still have to find a way to study it that makes me perceive it as useful time.

Since this is something I plan doing more in future, I already have several beautiful collections on my shelf (both real and virtual) waiting, but if this is my pace it will take me years!

I am now experimenting this 3 pass approach:
Step 1: scroll thru the game on lichess, reading the book comments. In this first pass I mark two or three variations that the author commented in the book.
Step 2: I go to the variations I marked, still using the lichess study, and I practice visualization on those. I go thru the whole sequence in my mind, without moving pieces on the board. Once I'm able to do the whole variation in my mind, or part of it in case it's too long for my visualization skills, I create the variation in the study.
Step 3: final pass in "guess the move" mode. I go thru the whole game guessing the next move, if I can't guess one move I try to narrow down to two or three reasonable candidates.

I started today testing this "sequence", and the first result are positive. The first game kept me busy for about one hour, and it was a more interesting experience than my previous. Will update this post as I go thru more games with this technique.

This is the study I was referring to:

One trick that I can suggest, is to leverage the many free studies available on lichess that cover the most relevant and famous games collections. It saves the time to go thru each game and map it into the study, plus it saves the time to backtrack thru the game when some move was not correctly captured. Lichess allows cloning a public study, my suggestion is to clone it and work on the clone, se we can keep track of the variants explored.