The expression Monday Morning Quarterback describes a person who says that they would have done something differently and better than what someone else did. The term originates from Sunday being the day when most football games are played, and people talking the next day about how they would have done better plays, made better calls, etc., than the actual quarterback.
Although the term originated in football, it isn’t exclusively used when referring to it. You may e a Monday Morning Quarterback when referring to how a colleague’s presentation should have been given (“I would have used a blue background on the PowerPoint”), or what a friend should have done at the party last weekend (“I would have asked for her number”).
Tomorrow when you are talking to your colleagues about tonight’s Super Bowl, please note the grammar pattern typically used by Monday Morning Quarterbacks:
modal auxiliary (should or would work best) + have + past participle of the action you would have done better.