"sloppy manner" is correct and usable in written English.
You can use it to describe someone's behavior or approach to something that is not done carefully, neatly, or skillfully. For example, "He did the job in a very sloppy manner and missed numerous details."
Entrees were plated in a messy, sloppy manner and — it seemed — cooked the same way.
Airport customs officials were tipped off by the sloppy manner in which the heroin was packed on Hou's body, making him appear bloated.
Further, although "un" is often spoken as a nasalized schwa vowel in very casual situations, which could express a sloppy manner, it was also found to express interest, when spoken with a breathy voice quality.
He said: "It has wasted millions of pounds on a badger cull which has no scientific, animal welfare or economic justification and was carried out in an outrageously sloppy manner which would have been laughable if it hadn't cost so many badgers' lives.
Colin Jacobson from the DVD Movie Guide however, gave a negative review of the album, saying "Possibly the biggest problem with Ciao Italia regarded the sloppy manner in which the program was assembled.
A comical bully, Hal-Finn rails at customers for their sloppy manners.
Material once deemed unsuitable for children — sloppy manners, untoward language, families that don't match the "Leave It to Beaver" rubric, disobedience — is now considered by many to be acceptable fodder for children's literature, even in books for toddlers who have not yet learned what they should be doing.
Instead, it covers ground with which most Adams fans will already be familiar, and in a sloppy, inelegant manner that will leave admirers of Ellis's previous books sorely disappointed.
You're clearly packing it in a sloppy, inefficient manner, and in the process leaving huge empty spaces in which many other dirty plates, pots or pans could have been packed.
"On my last trip about two weeks ago, although I touched nothing, I was told that I was interfering 'in a verbal manner"' and subject to being "detained" for expressing concern about the sloppy way the jewels were being handled, he said.
The supervisory board of Mannesmann has been revealed as unGermanically sloppy, committing all manner of bureaucratic mistakes in the process of awarding compensation.
