Solder pairs of sequins in series using long lengths of wire that match your flower arrangement. Tin the stripped wire ends with solder before inserting through holes in sequins to prevent stray strands. Use flush snips to trim off wire ends after soldering. Repeat five times or for as many LED pairs you want in your design.
Unless you're color coding your wires, mark the positive ends of wire with a permanent marker so you can sort them later. Inspect your solder joints and double check your LED polarity one more time.