Spread out your tarp or newspaper and set your items on it.
Start spraying your bottle. Make sure the spray paint can is well shaken!
When you're finished, let them dry in the sun for an hour. Then spray on a second layer, and let them dry, again, for an hour.
When your bottles are finally dry, find a flower to place it in. I used a fake flower piece, but any kind should work.
Even with two layers, you can still see the outline of the bottle's name. I thought that was a nice, vintage-like touch. If you want to avoid that, then repeat step 4 a couple of more times.
I recommend spray painting different bottle sizes, and experimenting with what you like the best. I really liked this look, with one bottle bigger, and the other smaller.
They also look great as bookends!
Store the unused bottles in a container until you need them. Spray painted glass is extremely susceptible to scratches (just a fingernail can, in fact, scratch your creation) so handle them with care!