1 - Warm Up Effectively
The pre-match warm up is key and usually indicative of how the team will perform during the match. Make sure your players are arriving well before the game (30-45 minutes before.) When all players arrive, set up practices that exercise body and mind all in one; such as a dynamic warm up (SST warm up!!) After players are loose and stretched, make sure they get as many touches on the ball as possible. You can do dribbling, passing, a little possession, or a combination. If there's time as well as a goal, finish with a little functional work for the strikers and midfielders on goal. The defenders can shoot, but it may be more beneficial if they work on longer passes together.
2 - A Little Psychology
Pressure to perform can inhibit your players' ability to be at their best throughout the match and can also cause a slow start. It is important to get players in a positive mindset before the match starts. This can be done through words of encouragement throughout the warm up as well as keeping everyone loose.
3 - Tactics
It is very important that your team knows the game plan going into the match. When the team has a clear objective (i.e. pressure high up the field for the first 10 minutes) it makes it easier to focus and perform well.
4 - Attackers are Defenders Too!
A problem with assigning positions to young soccer players is they take you quite literally. If you tell a child he/she is a defender, he/she will think the only responsibility is to defend and nothing else. Similarly, a child being told he is an attacker, forward, striker, etc. will think he/she doesn't have to play any defense. It is important to make it clear that everyone has a role both offensively and defensively.
5 - Don't Dive In!
When the ball is near your own goal, it is very important that players know to not dive in. The defender closest to the ball (the first defender) does not have to win the ball unless the opponent takes a bad touch and gives you an opportunity to put in a tackle.
6 - Let's Work Together
It is common knowledge that we want our defenders to outnumber their attackers so we can win the ball back. While the first defender is putting pressure on the ball, the rest of the recovering defenders should get behind the ball to provide cover for the first defender in case he/she gets beaten.