Paraffin oil, or mineral oil, is available in stores. It's sold under a variety of names. You can usually find mineral oil in the pharmacy department or paraffin oil within the home decorating section of your local big box store. Paraffin oil is an alternative to the lantern oils, as it's cleaner and burns smoother. If spilled, it won't flare up and extinguish, for the most part, rather quickly.
Remove the lid from the jar. Set it aside. Fill the bottom inch of the jar with glass pebbles, decorative stones or gravel. Arrange the silk flowers as you like with the bottom of the stems pushed into the pebbles. Don't have any of the silk flowers within the top 2 inches of the jar.
Pour the paraffin oil into the mixing bowl. Add a few drops of the food coloring and stir with the wooden spoon, if desired, until the paraffin oil is the desired color. Add a few drops of the essential oils and stir with the wooden spoon, if desired, until you have achieved the desired scent.
Pour the scented, colored paraffin oil into the glass jar until the oil level is 1/4 inch below the top of the jar. Carefully put the jar to the side for now.
Punch a hole in the top, center of the jar's lid using the nail set. You may need to use a hammer to bang on the end of the nail set, depending on the density of the jar's lid.
Cut a piece of the cotton wicking thread approximately twice the height of the glass jar. Thread the end of the cut wicking thread through the hole in the jar's lid. Place the long tail of the wicking thread into the jar of paraffin oil and screw the lid onto the jar tightly.
Don't let the level of the oil go lower than 2 inches below the top of the jar to ensure proper burning and avoid the wick from burning too quickly.
Always use the proper precautions when working with oil and flames to avoid injury.