You might remember the meaning of the character 或 with this easy mnemonic:
In a video game, the player has to choose one (一) of two random weapons when he reaches the mouth (口) of the first dungeon. Which would you pick? Halberd (戈) or poisonous dagger?
Using mnemonics to remember the meaning of Chinese characters like has a huge impact on how long to learn Mandarin it takes.