How do you learn and remember 左 and 右?
Did some research, but all I can find is that both 左 and 右 are actually the same symbol that denotes hand but reversed horizontally in ancient times. This symbol basically formed the top part of the character, which now pointed at same direction.

When I was in kindergarten, my teach used to help us to remember them by telling us 右 has a 口 in it, so it's the hand you use to hold chopsticks and eat since at the time left-hand dominance was considered to be corrected. That's why in China, you almost would not see people write or hold chopsticks with their left hand even it's their dominate hand.