There are three broad managerial functions: interpersonal relations, information processing and decision making.
Interpersonal relations include the roles of leadership and motivation, perhaps the most important managerial attributes. The way in which the football manager treats his players can affect not only the performance of the individual player, but also the performance of the team.
In the information-processing role the manager will use match reports and videos to analyse and assess the performance of players, in order to formulate plans and strategies. It is also likely that the manager will delegate responsibility, by employing coaches and scouts, to help disseminate information.
Finally, the decision making role involves determining the organisation of the team (team formation) and the role of individual players both before and during the game (pre-match and half-time team talk and strategic substitutions). The manager's ability to respond rapidly to situations such as a player suffering a loss of form or an injury can of course make the all the difference between the team achieving success or failure.