I was asked to make a ruling at a league the other day involving forgetting to take an action. Many of the younger players forget to draw their cards at the beginning of their turns. It isn't once or twice, it is usually until they play their last card, then realize they have not drawn for 6-7 turns in a row. Drawing an extra is game-play error: minor so would forgetting to draw be the same? I have found that cards like copycat, and any pokemon that knows "pull away" as an attack are not used much due to the small hand size of these players. My decision, since it was just league, was this: If the player has taken ANY action, then realizes that they forgot to draw, their turn ends immediately. It's harsh, but the players began to remember very quickly. Again, in the event that this happens at an event, what would be the appropriate penalty to give?