You might remember the meaning of the character 厦 with this easy mnemonic:
This tall building is even higher than that cliff (厂). One (一) can go up to the cliff by oneself (自), but you should go (夂) with caution, go slowly (夊) up to the top of the cliff, and you will see that you're only half way up the building.
Using mnemonics to remember the meaning of Chinese characters like has a huge impact on how long to learn Mandarin it takes.