use a sharp scissor to cut the bottles into leaves... make an oblong and trim the edges to form them into serrated leaves (or zigzag).

paint the petals for the poinsettias - red and for the leaves - green.
assemble now the painted petals and leaves by layering them to form poinsettias using your hot glue gun.
i made 5 poinsettias and arranged them on a circle made of cardboard :)

finally, put a ribbon to add more elegance on the wreath itself...and you're done!

p.s.
took me a while to finish my creation as i need to have the paint dried completely before putting them all together to form the wreath :)