I realised after posting the post above I left it a little unfinished ... so here's some clarification. Anyone who does this for every game increases their chances of performing better and setting themselves apart from everyone else. They will increase their assessment marks and their club marks. They will get a reputation for being reliable.
- do train to be fit enough to referee
- do close dates well in advance (minimum of 8 weeks if possible, as birthday/anniversary/wedding invitation dates never change)
- do make yourself available as often as possible and try not to turn down any invitation to referee/assist
- do treat every game with respect
- do acknowledge appointments promptly
- do submit any reports promptly, especially disciplinary reports but also any league reports required
- do use spell check when sending e-mails to everyone
- do always wear clean kit for every game
- do make sure you are wearing the right boots for the surface you are refereeing on (concrete, very hard, hard, soft, very soft, porridge)
- do clean your boots before every game
- do prepare your kit bag at least the night before a game and check it as soon as you get up
- do arrive in plenty of time for your game, which means planning your journey and any pick up times with sufficient spare time to cover any issues
- do carry important phone numbers in case of issues, such as home team sec, appointments sec, league sec and your coach/mentor
- do be seen to carry out your pre-match duties to an appropriate standard
- do brief your team properly, using notes if needed
- do warm up properly
- do take control of your game
- do read the assessors handbook and referee to that book (and the Laws of the Game)
- do deal with breaches of Law 4
- do ensure substitutes are controlled and take place at the correct place
- do be seen to be dealing with players using swear words (note deal with, that doesn't mean send every one of them from the field)
- do drink enough water each day to stay properly hydrated
- do seek advice from senior, more experienced colleagues
- do seek advice from your RDO
- do seek advice from assessors
- do attend your local RA meetings
- do train as an assessor
- do train as a tutor
- don't fail to take a mandatory disciplinary action, e.g. delaying restart
- don't let your game control you
- don't accept dissent
- don't think playing a lot of advantage will make everyone like you
- don't leave your sense of humour in the changing room
- don't post on Facebook, Twitter, blogs or forums celebrating how many players you sent off/cautioned
- don't post anywhere using information which will allow your games to be identified
- don't referee while injured, you may do damage which has a negative impact over a longer term
- don't drink alcohol on the day before your games as it can cause you to be dehydrated which leads to a higher incidence of injury
I'm sure there's plenty of other things you should and shouldn't do, but that will do for now.