You might remember the meaning of the character 郊 with this easy mnemonic:
I live in the suburb, where it is impossible to get even a cookie jar lid (亠) without having to walk for eight (八) miles through the jungle while being slashed (丿) by vines in order to reach the city (阝).
Using mnemonics to remember the meaning of Chinese characters like has a huge impact on how long to learn Mandarin it takes.