So here's something fun. Not only can one enjoy the process of procuring the materials needed for this craft, but enjoying the fruits of your very hard labor is pretty!
Simply take some bottles that have been emptied... If I remember correctly, the bottles in question here were a basic red wine, some delicious raspberry wine we tried once, and some gin. Delish. Rinse them out well, and remove labels, if possible. Here, the light blue gin bottle (let's call it sapphire, okay? hint hint) does have some etchings on it, but that's fine. As for paper labels, sometimes it takes a good soak in very hot water (rinse and repeat) and there are also a bunch of products out there that can take off any remaining gooey residue.
Pick a flower to showcase. It should be tall enough for whatever bottle you choose. For me, sunflowers are a beautiful representation of fall with their range of colors from bright yellow to burnt orange, and the stalk is tall and thick enough to give it all the support it needs.
Fill up the bottle with water (I'd say halfway is fine) and some of the 'food' packet that comes with it. Remember to change the water from time to time, adding more food, as this will prolong the life (okay, prolong the inescapable death that has been bestowed on said flower since it was ripped from the ground....) of your project.