Hi Harry,
Welcome!
As the others have said, try to relax and be as confident as possible.
Regardless of the age group, your pre-match routine will be pretty much the same. Pitch /goal inspection, quick hello with both managers, players equipment check, warm up, pre-match handshakes, toss the coin and away you go....
If you're lucky, the club linesman will make himself known well before kick off giving you an opportunity to pass on your instructions/expectations. Unfortunately sometimes you get to kick off time and the parents are still arguing who's turn it is this week, whilst you, the players and managers are standing around waiting for kick off!
Try not to let the thought of parents/coaches worry you. I have ref'd for my son's teams for the past 5 years, there's good days and some very bad days. Some parents/coaches are great, others are complete idiots. Either way, you learn to filter out the garbage and only listen out for "ref, can I make a sub please?".
Funny in a way from the first to last whistle, you are the enemy, everything you do will be wrong as far as they are concerned. Don't let it get to you and take it personally (can be difficult I know) Full time whistle goes, it's usually all smiles from the very same people and "thanks ref, did great job!"
Couple of years ago, I "retired" from refereeing, partly because I became disillusioned, frustrated and fed up with the abuse and idiots on touchline, I had lost my ref'n mojo! During my 9 month break from refereeing, watch plenty of games. Enjoyed it at first, no pre-match pressure, could just turn up, watch the match and go home without being the centre of attention/abuse etc. The longer it went on, the more I realised I missed it, became frustrated again, stood there thinking some games "I was better than that cheating/useless idiot", "I can still do this and make a difference" etc etc. About 6 months into retirement, had my arm twisted to help out last minute, thought go on then if I must. Was another 3 months before I ref'd another game. Still had a few thoughts of "what am I doing? and "must be mad" especially when the away team for that game had a terrible reputation on and off the pitch and rightly so having witnessed some of it first hand as a ref and spectator on several occasions. Went out there and absolutely nailed it, it was great to be back!
You/we all make mistakes (some more than others), learn from them and come back stronger.
Enjoy it and whilst your in the middle, you can make a difference! There are plenty of idiots on the touchline who think they can do a better job, very few have the balls to go out there and put their money where there mouth is!
Good luck!
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