cut a hog: make oneself look foolish by attempting a project beyond one's capacity
Other versions of this colloquialism, popular in the early decades of the twentieth century, are cut a hog in two or even more colorfully, cut a big hog in the mouth with a small knife. The expression may have originated in the African-American community. It appears in Zora Neale Hurston's 1937 novel Their Eyes Were Watching God, where it seems to convey the general idea of making a mistake: "This is the last time you gone come in my house and cut a hog, then turn around and like you ain't done nothing wrong."