What about ק qof? The letter resembles a capital "P" in English...yet it can be transliterated with a "Q". Just "mind your P's and Q's" would be our mnemonic. One word using , qof, is קול qohl, meaning "voice, sound". It sounds like "coal", which for miners, the dust can make their VOICE SOUND raspy. It is hard to breathe in that coal dust! To remember that it is spelled with the ק , qof, know that all miners must still "mind their P's and Q's" and be very polite and courteous, watching out for each other for safety's sake in the mines.
Note that the words I used today כל קול are also homophones. My mnemonics work great for keeping straight how to spell each of these words that sound the same. You can make up your own mnemonics, too! I would be excited to see what you may come up with. Comment or email me your ideas, and I may feature them in a future blog.
* Sorry, I don't know how to add dageshim to letters with my keyboard.