The Ring Bearer has these duties to perform at a wedding
Attend the rehearsal
Arrive at the ceremony at the scheduled hour
Walk in to the ceremony bearing rings on the pillow
Pay for the wedding attire, accessories.
Pay for travel and lodging expenses (latter could be borne by the couple)
It might be a good idea to use fake rings or some kind of a substitute to avoid the ‘real thing’ getting lost. By virtue of their designation, your attendants are there to attend to the couple before and during the wedding. So involve them as much as possible and delegate as much to them so that you are able to relax and partake in the merriment and joy of your wedding to the hilt.