There is only one way to start a game: a KICKOFF. Before the start of the game the referee flips a coin and the visiting team will call the flip. The winner of the toss choses what goal they will defend (or which way they want to go). There is a greater advantage to chosing sides than a kickoff, hence the choice of goal to defend.
There are different ways to restart play when play is stopped.
Recalling the markings mentioned in Law 1, remember that opposing players must be a certain distance from the ball when a team is awarded a free kick (allowed to kick the ball from a stationary position). For fouls committed (discussed later), a free kick is awarded. The team awarded the free kick may, however, decide to do a "quick restart," without having the opponent at least ten yards away. This is allowed, but the player may not object if the other team steals the ball after the touch, because they were closer than 10 yards away.
If the ball crosses the touchline (side) last touched by one team, the opposing team is awarded a THROW IN (discussed later).
If the ball crosses the goal line,
1.) If the offense (not the keeper's team) last touched the ball, it is restarted with a goal kick, which is placed anywhere within the goalbox (the smaller box by the goal) and kicked back into play. Note that the ball must go outside the penalty box (the larger box) before another player may touch it. If it doesn't go outside the penalty area or someone touches it before it goes out, the goal kick is retaken.
2.) If the defense (keeper's team) last touched the ball, the ball is kicked into play from the corner (closest to the side it went out) by the offensive team. There are quarter arcs marked at each corner for this.
If the referee stops play due to an injury or a reason other than the above and not the end of a half, a drop ball is used to restart. One player from each team is allowed to be there and the referee drops the ball between the two players. There is no requirement for players to be there for the referee to drop the ball, though this is rare.