One of the hardest things for a team to do is to field the same team at every race or regatta. Inevitably someone cannot make the event and the team has to adapt with new crew. This is a reality of life that just about every team has to adapt to.
As a coach I recognize this fully and have formulated team position charts for different types of boats so that the team has a blueprint on how to plug in someone new as seamlessly as possible. The most challenging scenario very often is on bigger boats where there are more team members and very often more complexity than smaller boats' teams experience.
The position chart that I use as an example is for a J120 team sailing in PHRF. Like all the charts, is very flexible in terms of how it is applied as regards to the experience level of the new crew and who they may be replacing. You can see this sample chart by clicking this link.
The chart has been very useful as a training tool in helping develop the foundational structure of the teams individual responsibilities around the race course. In some instances I have expanded it to include roles at the dock prior to and after racing, roles and a check list in between races (who packs the spinnaker, who keeps the boat close to the starting line, etc.), as well as the team debrief with a team member taking notes or filming the session.
To start developing your own chart, I recommend interviewing each team member on his or her role going around the race course. Fine tune it, and then implement it in the next practice session or in the pre-race practice session. The chart is continuously developed and fine-tuned after each regatta and really does help provide a blueprint for who does what when—especially if you notice three people up on the bow during a Spinnaker takedown doing one person’s job!