Soccer coaching is an extremely rewarding and fun experience for anyone who has had any involvement in soccer before or played soccer.
Depending on the age and playing level of the athletes, you may not need to learn everything right away. You can study the basics by reading manuals on the rules, basics of the game, and penalties. Then you can watch other games and learn something from other coaches, either local or televised, to get a feel for the rhythm of the game.
Below is a list of resources to help you along in your coaching abilities. Knowing why a drill is important is just as important as doing the drill, if you have any questions feel free to contact other coaches in the league for advice.
National Soccer Coaches Association of America
Michigan State Youth Soccer Association Instructional Videos