Charter Members

As most of you know I am church planting in Texas. Recently, our church received confirmation from the state that our tax-exempt status has been approved following the filing of our constitution and bylaws. The elders want to have a Sunday morning celebration dedicated to the "founding" of our church. We have people attending, of course, but no official members. What procedure would you use for creating charter members at that service and going forward? Would you use that morning as a membership class of sorts, sharing your vision, goals, core values, etc? Would you ask them to become provisional members by acclamation and/or sign a celebratory document that recognizes everyone that day who would like to become part of the church? Would you pass out individual membership covenants to sign right there and then or to sign after future consideration and prayer? I'm looking for ideas. How would you do it?
- Daniel