Arremangado literally means "rolled up sleeves," but in this context, it's used colloquially to mean "gotten to work" or "put in effort," often implying a readiness for a challenge or hard work.
Larry Hernández uses it to suggest he's been a busy man, perhaps even a bit of a ladies' man, but with the woman he's singing to, he wants to make an exception and settle down. It's a colorful and engaging word that paints a picture of his past while setting up his intentions for the future.
Get ready to meet a guy who knows what he wants and isn't afraid to show it! Larry Hernández brings us "Vete Acostumbrando," a song where he's laying all his cards on the table for the woman he's pursuing. He admits he likes "lo bueno" [the good stuff], and that's exactly why he's after her. He sees her as a "monumento" [monument] and he's ready to be her "hombre perfecto" [perfect man]. He's even willing to make an exception for her, moving from simple "tortillas" to a "platillo mejor" [better dish] when it comes to love.
He's not shy about telling her to "vete acostumbrando" [get used to it] because his love comes with a lot of personality! This means late-night serenades with a band so loud it makes the windows shake, even if the neighbors call the police. He wants her to get used to his "detalles" [details/gestures] and tells her to inform her parents they have a new son who will take their daughter "al cielo" [to heaven]. He's also upfront about sometimes coming home "pedo" [drunk], because that's when he'll truly say "te quiero" [I love you], admitting he has a "roca" [rock] in his chest. It's a bold, funny, and very direct declaration of love from a man who's ready to shake things up!