THERE is an alliterative saying I learnt in the Air Force: Prior Preparation Prevents Pretty Poor Performance.
  The 6P Rule is central to many things, especially those requiring structure and excellent organisation. Why? Because if you don't get it right, every one of the participants will know you have dropped the ball.
  The first necessity is to know exactly what you want; will you provide lunch, include accommodation, include freebies such as brief cases, package the conference with discount airfares, hire cars and a trip to a local tourism venue? What about spouses and partners, will they be included? Once you know exactly what you want ... and it's a sound idea to contact several venue providers to ask what they will do for what cost, make sure you have a written agreement about:
  what you want
  when you want it
  where it will happen at what cost
  who will carry out the various roles/activities
  what will happen if something goes wrong (contingency plan)
  Once you have agreed what you want and the venue provider has agreed to provide it, you are on your way. Or are you? You aren't, because there is much more to do ... like communicating with the intended participants ... the reason for the conference.
  You need to be explicit in what the conference offers, how people nominate and pay, when it will start and so on. In fact what you should do ... mentally, is think through the various ways and options for people to attend. Go through each step and ask yourself, 'What happens here, how will it be handled?'
  Imagine yourself writing a cheque to pay your nomination ... where will you send it, what will happen once it is received? By doing this mental thing, you can identify 'fail points', which may prevent embarassment and inefficiencies somewhere down the track. For example, incorrect payee details on a cheque will require you to contact the sender and have another cheque raised ... all valuable time and resources wasted.
  Make sure participants are fully aware of what they are expected to do and what you, the organiser will do. Don't allow any room for errors.