Typical preparation is to make an infusion of the bark or root and drink the infusion as a calmative. Other methods include preparing a tincture, which is then consumed in small amounts.
It's compared to Kava... Hmm, this is a very interesting new drug I haven't come across of heard about until now.
I'd try boiling some water, taking the water off the stove and letting some root/bark shavings steep in it. After it has cooled filter the stuff out and drink up.
That's just my generic way I make tea out of herbals/drugs. It generally doesn't pose any problem because it isn't too hot to degrade most alkaloids yet will generally, although not always, do the trick in terms of extracting whatever you want from the solid/tea.