An even better memory aid is having an English teacher who for a whole term made the class stand up when he entered the room (as was normal when any teacher entered the room) and instead of the usual "Good morning class.", "Good morning Sir." ritual made us chant in unison "It's with an apostrophe means IT IS!". To this day, fifty odd years later, if I ever have a moment of doubt about how I should punctuate "its" I can hear a whole class chanting in my mind's ear.
Reading you all, I am stunned to realized that it is actually a difficulty for the natives to know which is which ?!
I mean an apostrophe to me I always learned it was just a short for "it is" or "do not"... so " its " not having an apostrophe obviously has to mean something else, so I can't possibly mix the two. Maybe I am strange... but I don't see the need to have ritual to remember something as simple ?!
What I don't master however... is when people say something like " it's changed " instead of " it has changed "..so that means "has" can represented as an apostrophe like " is ".... or maybe not ? Maybe " it's " always means "it IS "... but in this case I don't understand why they would say " is IS changed " instead of " it HAS changed "... it is instead of it has.... happens regularly but I don't yet get when one would say " it is changed (for example) " instead of the more normal/usual " it has changed "..... there must be something to it, either a grammar rule or some habit, but I can't figure it out on my own....
While we're being 'correct' about apostrophes I might point out that an aide is a person who assists whereas a memory technique is spelled aid without the 'e'. You can probably blame the borrowed French "aide-mémoire" for your slip. I would were I you.
That's funny... so looks like this word has not yet fyully morphed into English, you have only partially dropped the ' e ' ! Confusing for sure, I understand the pain it must be.
Here of course no such pain, " aide " is always written this way, be it the verb or the noun no matter if it's a person or an object or whatever...
That should teach you : if you want to use a French word, just use it as is and you will be fine, don't try to simplify/modify it !!!
That's what we do here... whenever we use an English word, we just use it as is, we don't try to French-ize it... We pronounce it in all sorts of weird and ridiculous ways but the correct one, we often don't really know what it means... but at least we don't try to modify its spelling. Well, maybe someone can come up with an exception to that but generally pseaking speaking I would say it holds true !
A sandwich is still a sandwich, a weekend is still a weekend. OK you are allowed to write it " week-end " if you want, but still...