The fastest way to learn the rules of a game is to lose a lot. Same with most skills.

Losing is informative in a way winning never is. A defeat tells you exactly which rule you had not understood, which habit the other side could exploit, which part of your plan only worked against nobody in particular. Winners often cannot say why they won. Someone who has lost forty times can usually describe the game in detail.

Play people better than you on purpose, and keep a short note after each loss about the one thing that beat you. Look for the repeats across a month. Stop treating the scoreline as the result and start treating the note as the result.