These tricks are not exclusive to Japanese alphabet. I also used them to match with Odia alphabet and south Indian alphabet to remember. Check this out !
い ଇ ಇ ఇ
The “i” [said as e, as in english] has a component which is partially same (two circles, if extrapolated) in Japanese, Odia, Kannada, Telugu. That is actually how I remembered. Even in Odia, Kannada and Telugu the “i-symbol” is same.
Check: ଦି ದಿ ది [I have written phonetics di as in “the” in Odia, Kannada and Telugu] The vowel “i” which is written as a symbol on top of the letter is same in all cases, so that helps to remember what the letter is reading. [I already know my native speak Odia, so its much easier for me to remember this way]