For longer outings and more adverse conditions, not a bad idea to let someone on land know what your planned route is and when you should be back on land at any kind of reasonable pace. (give them a call if you get off track schedule wise, and call them when you get back on land). And there is always the unexpected so you may want to let someone know where you are going even when you think conditions are benign.
Now is the time to express any doubts about whether any group member shouldn't be paddling in the given conditions. This is not just an assessment of anyone's paddling skill - it is also an assessment of the other group member's ability to provide support and rescue in the current conditions.
Make sure that everyone is buddied up
If anyone is not planning to stay with the group, speak up now. And make sure everyone knows that anyone deciding to leave the group while on the water needs to communicate this before separating from the group (or make a serious effort to communicate their situation if they inadvertently get separated from the group while on the water)
What Are the On-Water Plans?
In bigger conditions it may be advisable to plan to keep all of the groups of buddies reasonably close together or at least have some paddler backups for the buddy pairs with weaker paddlers.
Will there be a group check point where the front runners will stop, wait for everyone else and address any issues or any need to change plans. Wondering where someone else is and constantly trying to look for them when you think they might be in trouble and can't see them is way more work and stress than having group gathering points.
See “Mobile Phones and Apps” below. Have phones and using SafeTrx? You may be able to track everyone and see how far they are away and whether they are moving toward you or not.
Everyone's radio is turned on and on the same channel?
You have an alternate channel chosen for non-emergency communication?
Discuss alternate plans if main plan falls apart? Have an alternate plan for land fall or mission reversal/shortening if initial conditions prove more difficult than expected or if conditions worsen during the outing?
Mention/discuss the fact that there are other local bodies of water that can provide downwinding more safely on really big wind days and might be the better option today?
Everyone has a buddy and they are leaving shore together?
Buddies check each other's leashes are attached to body and boat?