Aplícate el cuento
 

In English?
Aplicarse el cuento, ejemplo:

- Deberías de fregar los platos que uses cada vez que comas algo.
- Ok. Aplicáte el cuento tu también ( meaning you should do the same )

Most commonly we would use "you should do the same", but there is
an idiom. That idiom is to follow suit.
It is formal sounding. example: I got the flu shot and I suggest that you follow suit.

One verse of a nineties song of Genesis said "just do as I say, don't do as I do"... if it's not an idiom, it should become one. :D

Hay un dicho, " monkey see, monkey do". :D Supongo que me parece parecido:)

"Do as I say, not as I do" is the idiom. 1,760,000 Google hits vs 6,000 for the Genesis lyric.

I like you shoul follow suit the difference is that in Spanish" aplicate el cuento" implies a little bit of critics

Thank you, pjt, Google's hits are a useful tool I always forget about. :D

Anyway, apart from idioms, it would be easy to reply "yes, when you do the same as you preach, we'll talk about it".

The idiom for that is "Practise what you preach".

That one is a good one, it conveys the same idea.