You can use a glass spray bottle, or try using an empty (or almost empty) 15ml essential oil bottle.
Add 2-3 drops of essential oil to the bottle. I love Serenity, but Lavender, Cedarwood, Thyme, Frankincense, or your favorite relaxing oils work well, too.
Fill the rest of the 15ml bottle with distilled or cooled boiled water. (Be sure you leave a little room at the top for the sprayer.)
Add a pinch of Epsom salt, if you have it. (This will help the essential oil to mix a little better with the water.)
Put on the new spray top. (Contact me if you need one.)
Gently shake to mix the water and essential oils.