Rosemary, Thyme, Oregano, Lemon, Wild Orange, Lime. Do the names start you thinking about a good marinara sauce, lemon squares, wild rice with a hint of lime? Many of the essential oils can be used in cooking. In fact, there are 6 recipes in the latest edition of Modern Essentials just to get you experimenting. I recently added a drop of Wild Orange to a chocolate frosting I made for a cake fundraiser. It tasted wonderful! Just keep in mind the oils are potent. You can simply put a toothpick in the bottle and then apply it to a part of the food you're cooking and come out with a great taste.
You can easily add a drop of oil to 1-4 cups of water, almond milk, rice milk, or even hot chocolate. If it's something you'll be sipping on throughout the day keep in mind the oils are powerful and potent. Use glass when possible, as plastic can begin to deteriorate, and as the oils will tend to sit on top of your liquid you'll need to stir or shake it up before drinking.
What if you really don't like the taste of the oils you want to take internally? DoTerra has come out with Veggie Caps, which are 100% vegetarian and come apart so you can put in which ever oil you'd like. If the oils feel too strong even after you've swallowed them try adding some Fractionated Coconut Oil (which can be found through doTerra) or Extra Virgin Olive Oil to the capsule. Don't take too long to swallow them as the capsule will begin to dissolve.
Don't worry, I didn't know what it meant at first either. Sublingual is a really fancy word for "put it under your tongue." "Because the blood capillaries are so close to the surface of the tissue under the tongue, many essential oil constituents are able to pass directly into the blood stream from there, where they can then quickly travel to the different areas of the body where they are needed" (Modern Essentials, Fourth Edition, pg. 39). Keep in mind taking oils directly under the tongue will be a powerful experience in taste which, depending on what you like and don't like, could be very good or very, very bad.
To be sure an essential oil is safe for consumption look at the bottle. If it lists Drug Facts you're safe. If not, do some research to be certain. Though Citrus Bliss does not list drug facts, many use it in their water.
A few ideas:
Jennie adds a drop of On Guard to the hot chocolate she makes for her family during flu and cold season.
Laurie sips on water with Lemon and Peppermint to help detox and cool her down. It also helps with heartburn.
Amanda takes Slim & Sassy in the veggie capsules, as she doesn't like to sip on it.
Michelle puts a drop of Melaleuca on the back of her tongue, then drinks some water to help her sore throat.