Line a sheet pan with waxed paper. Cut 1-inch off the end of each banana. Insert a popsicle stick into the cut-end of each banana, pushing the stick halfway in, leaving the other end exposed for use as a handle. Place the bananas on the sheet pan and freeze 1 hour.
Melt the chocolate and butter in a bowl over a saucepan of simmering water, stirring occasionally.
Arrange the dipping decorations on several flat plates. Working with 1 banana at a time, dip it in the chocolate and turn to completely coat (spoon some on, if needed). Roll the dipped banana in the desired decorations, transfer to the sheet pan, and return to the freezer.
Once frozen, store the bananas in an airtight container.