Its completely up to you Hun, i haven't been to a wedding without one though
This includes, both parents names, bridal party names, readers names, your vows, celebrants readings etc etc.
Here is an example from another WC post i think
Page 1 - Welcome to the wedding of etc
Page 2 - Wedding Participants and their roles
Page 3 - Order of Service and I have left this to be one line each eg. Entrance of Bride, Introduction, Celebrant's Authority
Page 4 - The words to "Ave Maria", the song I'm walking down the aisle to
Page 5 - The words to our reading
Page 6 - The words to our "hand blessing"
Page 7 - Thanks