After Your Match
Aside from the obvious packing away stuff that needs to be done after each game, the one thing you absolutely have to do after your match day is to submit your match report to the league.
This takes the form of confirmation of the score, sportsmanship scores for the opposition and whether there were any disciplinary issues (hopefully not!). Details on how each league handles this process:
Submitting Results:
For mini soccer age groups (U7 - U10), see the Crowborough League website for what you are meant to do. It changes sometimes, so easier to check with them.
From U11 upwards, the leagues require you to submit your results and match details / sportsmanship scores via FA Full Time
Sportsmanship Scores
Different leagues handle this differently, but you will be expected to give a sportsmanship mark to your opposition (and they for you). This won't be seen by them, but will give the league an idea of any teams who are perhaps getting consistently low marks. They may send a random observer along to a game if that's the case. At the end of the season, the team with the highest marks gets an award.