Are there better ways to say “Don't make the same mistake repeatedly.”?

The slightly more idiomatic/lively version is "don't make the same mistake twice". Not sure why, that's just how it is Along these lines we do have a phrase, "fool me once, shame on you. Fool me twice, shame on me"

A side-note: it is incorrect to pluralize “slang”. You can say “slang phrases” or “slang words”; there is no such thing as “a slang”.

Learn from your mistakes so you don’t repeat them.

We say “don’t make the same mistake twice” or “stop making the same mistakes”. I can’t think of any idioms. The only thing that comes to mind is “fool me once, shame on you. Fool me twice, shame on me”

"Don't make the same mistake twice." Is the most common related phrase. Other ways I would convey the same meaning: Don't repeat your mistakes Don't keep making the same mistakes Don't let history repeat itself

Learn from your mistakes

"Fool me once, shame on you. Fool me twice, shame on me" maybe?

Wait is there an expression "don't step on the same rake twice"? Asking as a non-native speaker

“Don’t fuck the same cactus twice” came immediately to mind, but I don’t think I’d recommend using that under most circumstances.

Not exactly what you described, but: Fool me once, shame on you; fool me twice, shame on me.

Learn, monkey, learn!

Some idioms, from various times and places. Once bitten, twice shy The burnt child dreads the fire. A lesson earned is a lesson learned. Fool me once, shame on you. Fool me twice, shame on me.

It should be slang, never slang"s" by the way

Some people say the definition of insanity is doing the same thing over and over again and expecting a different result. You wanted something that sounded more casual though, so the way I’d say this is “don’t keep making the same mistake” or something along that line

There is the Santayana quote “Those who forget the past are doomed to repeat it.” That is a more flowery way of saying it, with maybe a somewhat different meaning (it is not the same person making the mistakes).

"Fool me once can't get fooled again" but you have to say it in a southern accent...

"Stop banging your head against the wall'. Or "The best thing about banging your head against the wall is when you stop"

No sense beating a dead horse.

My personal fave is "fool me once, shame on you. Fool me, twice well ya ain't gonna fool me again." (The original is "fool me once, shame on you, fool me twice, shame on me", the above is G. Bush quote showcasing how flexible and fun idioms can be)

Ben Franklin: "Experience keeps a dear [meaning expensive] school, but a fool will learn in no other."

"Over and over again" is a colloquial way to express 'repeatedly', so you can use that instead.

I think an emotional/frustrated way to say it would be "don't make the same mistake over and over again"

If someone keeps making the same mistake / messing the same thing up you would say "they're a slow learner".

Smart people learn from the mistakes of others. We grow too soon old and too late smart (said with a Yiddish accent by someone my grandfather’s age).

Learn to do it right on the first take

Seize the opportunities to improve

The First Rule of Holes: when you're in one, stop digging.

“Don’t do it again” is probably the most common one.

Don't repeat your mistakes 

Definition of insanity

"Don't let history repeat itself" is probably the closest idiom, but it more refers to the mistakes of others in the past. "Fool me twice, shame on me" is sort of in the right area, but definitely is different. Honestly, I would just say "Don't make the same mistake twice". Which stops working as well if they've *already* made the same mistake twice. "Don't make the same mistake again" could work in those instances.