You can make soap of it.
You can leave some where it is and occasionally rub your fingers on a flower and smell them.
In my head I made of this question: Things To Do With Lavender When You’re Dead.
A little bit can add a great aroma/flavor layer to cooking ^^ @Kardamom covered that, but be really careful with the amount. A little is wonderful, slightly more, and it tastes like soap.
I was told, long ago, that drying it and putting it in a (breathable) satchet under your pillow makes for a dreamless, healthful sleep. I have to try that.