You might remember the meaning of the character 誓 with this easy mnemonic:
I vow to find your killer and avenge your death by putting an umbrella (扌) and an axe (斤) through his head! I'll also put a lid (亠) or two (二) over his mouth (口) so he can't scream for help.
Using mnemonics to remember the meaning of Chinese characters like has a huge impact on how long to learn Mandarin it takes.