The most natural way we learn is by simply watching and then mirroring or imitating what we see. This is the way we learn as children. This is the way someone traveling to a different country learns how to live in a new environment. And so on.
That is why, in my opinion, visual tennis is one of the most effective methods for learning how to play the game. And, in my experience, it is also much more efficient; that is, it requires a lot less time, effort and money compared to other approaches.
Visual tennis involves carefully observing – live or videos – how proficient players play the game. Then visualizing this in your own mind in as much detail as possible. Then you go out and try to mimic the mental images in your mind. Then repeat as often as possible until your muscles remember what is in your mind.
To get you started learning the natural way, take a look at these videos for the one-hand backhand, the forehand, the overhead smash, and the serve. You can also spend a few minutes watching the biomechanics of this player figure. Important: watch these repeatedly to make sure you are observing as much detail as possible – the stroke motion, the foot movement, the body balance, etc.