What about the concise, memorable, and conveniently alliterative expression WHILE YOU WAIT, which is sometimes seen on business signs?
If someone can remember that three-word phrase (and the pictures I've added might help someone do just that), then it might be easier for them to remember how while would be the word that means "during some time interval."
Once you get one half of a confusing pair straight in your mind, the other half pretty much falls into place by default. But if you wanted something more, you could simply imagine the business owner saying:
I can fix this while you wait; you won't pay until I'm done.
The 'standard' order of adjectives is the Royal order of adjectives, memorised as DOSSACOM Q. This is standard across all varieties of English, and even non-English languages that allow prenominal adjectives.
Whether English users get it wrong is more difficult to answer. Underlying the royal order of adjectives is another ordering of determiner > specification > description > categorisation > noun. This is fairly solid, but within the three zones of specification, description, and categorisation the order is more of a tendency or preference than a rule.
This is because underlying that is the principle that the more concrete, intrinsic, or "nouny" an adjective is, the closer to the noun it goes. For example, if we compare the large round coin with the large round table, 'round' is very concrete. They are either round or they are not - there is not much to argue about and 'round' has the same meaning for both, so it is placed close to the noun. 'Large', however, is relative. A large coin is much smaller than a large table, and a table the size of a large coin would be considered tiny, so 'large' is placed far to the left of the noun.
There are limits to this. Size, length, and height are equally "nouny", concrete, and intrinsic, yet they appear in precisely that order, suggesting that it is mere convention. On top of this, deciding how "nouny", concrete, or intrinsic an adjective is, is quite subjective. This makes the whole notion of 'wrong' a bit cloudy, at least within the previously mentioned zones.
Best Answer
Your mnemonic seems good for its purpose.
You should know that the rule in question does have exceptions, and this is actually a shockingly complicated and controversial subject:
https://english.stackexchange.com/questions/1155/what-is-the-rule-for-adjective-order
As Jasper noted, most native English speakers are not taught this rule but instead absorb what sounds natural through osmosis. While the rule might be helpful for writing, I don't think you'll ever be able to apply it at conversation speed, and you should probably supplement it with repetitive practice of common multi-adjective phrases.