"to have your work cut out for you," which means to be facing an obviously difficult task, one which is as much as one person could possibly handle. ...
... the history of the phrase, which did originally refer to sewing. While having someone else follow the pattern and cut out the proper bits of cloth from which to sew a jacket, for instance, would no doubt be helpful, the most arduous part of the job is actually sewing all the pieces together. Today the phrase can be applied to any sort of work or effort, and "to have your work cut out for you" means that your task is clear and ready to be tackled, but all the more daunting because you can clearly see exactly what needs to be done.
"To have your work cut out for you" is a remarkably old phrase, dating back to around 1600, and occurs in Charles Dickens' "A Christmas Carol" as well as the works of several other famous authors.
get my work cut out for me - WordReference Forums
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