I’m not sure if I understand how this cantrip works. I really want to use it for silly things, like having my fun-sized -1 strength rogue smack a table indignantly, sending sparks flying everywhere and leaving a black mark on the wood, or sneaking up to a guard and soiling their pants, but that doesn’t really work, does it? My DM said that spellcasting breaks stealth, and that typically people can tell that I am casting something if I am casting something, so what would I even use this for, if I basically can’t use it to actually trick people? It wouldn’t even be possible to cheat at card games, since anyone could tell that I just did some magic. Am I missing something here?
It’s stage magic as a spell. It’s not designed to be subtle, the opposite in fact (though this isn’t to say that it can’t be, it just requires extra resources). You misdirect observers with sleight of hand and captivating personal presence so that they don’t quite catch on. It’s not hard coded in the rules how to make that work so you’ll have to work with your DM on that a bit, but it’s probably an easier ask than to just not be noticed at all.