BritishinformalHandle (something) incompetently:the taxi driver made a muck of it and took me to the wrong place...
Of course, if her side win today, Nilsmark will be remembered as the great master tactician, but if Europe slips to defeat, she could be accused of making a muck of her choices.
If Finnie makes a muck of it - as I'm sure he will - I wonder if Jack would look in my direction.
‘No, she's just made a muck of things, that's all.’