First, I got these candolier from Amazon along with the flickering lights. You can also get these at Hobby Lobby and other stores, especially around the holidays. They do come with clear lights but you can get any C7 light bulbs that makes you happy!
To start with, I put cotton balls in the light sockets to avoid paint spraying into them.
Next I taped some paper towels around the cord to avoid painting on those. Since most window seals are white, it would blend better leaving the cord as is.
Now comes the paint, MAKE SURE you use Fusion spray paint which is made for painting on plastic. If you use regular spray paint, it would just scratch off when you touch it AND it must fully dry for 7 hours to cure!
Doing two to four light coats will give you a smoother finish. Don't rush it!
After an hour or so, you can handle them with caution until they are cured - now, time to take out the cotton balls and take off the taped paper towels off the cord.
You are now ready to put your light bulbs of your choice in and turn the spooky on!!!