As long as you mix the ylang ylang essential oils with some carrier oil then you can apply the ylang ylang oil to your skin.
Don't apply the ylang ylang essential oil directly to your skin without first diluting it with a carrier oil because it can cause a rash or other irritation on your skin.
You can also use ylang ylang oil by inhaling it to help you sleep and help with the flu or cold by sprinkling a few drops of the oil onto a cloth or tissue, or by using an aromatherapy diffuser or vaporizer.
All essential oils including the Ylang Ylang oil should be diluted with carrier oils before applying them directly to your skin because they can cause irritation.
Some carrier oils you can use to dilute Ylang Ylang oil or other essential oils are jojoba, sweet almond, or avocado.