Having signed the booking form from the Fair Organiser, abide by its terms.
Once committed to a Fair do not back out unless it is absolutely unavoidable and let the Fair Organiser know as soon as possible.
Keep to the category for which you were invited and do not complain when asked to remove any items which were not included in the description of your stock on your application form. If your range does change between acceptance and the event, let the FO know well in advance what new lines you are hoping to bring.
If you have any special requirements please let the Fair Organiser know them well in advance, particularly if a power point is needed.
Cartoon by Dominic Minns
Do not encroach on your neighbour's space and be as considerate to other SHs as you would hope they would be to you. Keep to the table or area that you booked - if you paid for a single stall don't expect to be able to squeeze in a stall and a half with additional tables/stands/etc. unless your neighbours and the Fair Organiser are happy about your increased area.
Be as helpful as you can, at all times, to everybody around you.
Pay your percentage promptly and honestly. If you have a helper running your stall either make sure she has the means to pay the percentage or make prior arrangement with the Fair Organiser to pay it as soon as possible after the event. Do not take off any expenses unless invited to do so by the Fair Organiser.
Take your rubbish home. Leave your space/area clean and report any damage.
Do not pester Fair Organisers for space at their Fairs. If you are turned down accept it gracefully - all Fairs receive many more applications than they can accommodate and it can be counter productive to your future applications if you are too persistent in asking for space.