One of the men makes the announcements before our worship starts. For years, I have made an announcement sheet that contains the upcoming events, new people on the prayer list and those who are serving. Being in a military congregation, we have a monthly duty roster for those who are serving in worship.
Concerning the duty roster. One of our men puts the sheet on the board before the month starts, with the names of all those who will lead in worship. We mark when we will be absent and then he makes the roster for the month, so we know in advance who will serve.