From Lost Fables Wiki
Dreidam's primary ritual, and the best means by which to attempt contact, is through the Ritual of Understanding, which is an earnest attempt to grow in understanding of something. This can have a vast array of different specifics, but must follow the general idea. Generally this attempt must take place over about half an hour or so. As such, Dreidam's temples tend to be places of quiet contemplation and learning.
The Ritual of Truth is performed every morning, requiring a cant in celestial to ask Dreidam to lead one to the truth, or to a Truth which will help them in life. It can also be done before an altar to attempt to contact Dreidam.
A very prevalent ritual to pray to Dreidam is casting a friendly Truth within a church or nearby an altar of his, and praying to him afterward. This gives a plus five in the roll to contact the deity.
Like all celestials, Dreidam speaks almost entirely in signs, almost never giving answers in absolute. One must interpret the will of the celestials in most part...