Some bottles have vertical indents and you can use these to cut lines down to the base. If your bottle doesn't have any indents, divide into 5 equal sections.
Keep your cut a distance of 3cm away from the line that marks the cup shape at the bottom of the bottle. Don't worry if you get it wrong the first time - you can use the base for another project.
You can still make adjustments if the cut is too short.
Once dry, fold over the sections and add your desired embellishment - attaching on the top of one section with hot glue.
You can even decoupage your party favours with fabric or wrapping paper.