verb: 1. To do (something) badly; bungle (often followed by up): His interference bollixed up the whole deal.
noun: 1. A confused bungle.
People always bollix up the things that are most important to them.
- -- Eric Gabriel Lehman, Summer's House
It was a sort of cruel fun watching this guy bollix up his life, like watching a cat fight duct tape.
- -- Sarah Smith, Chasing Shakespeares
Bollix arose in the 1930s. It's a variation on the slang word bollocks.