@vargsvans has a good post including a section about mnemonics …it’s focus was different than that of this topic, but I think it’s still worth mentioning -
It does involve creating your own mnemonics, which takes effort, but it helps avoid mix ups when WK uses different mnemonics for the same sound (e.g. ぎ can be either guitar or guillotine), or the same mnemonic for different sounds (e.g. row for りょう and ろう). Anyway, it’s better and more thoroughly explained in the post…