"To divination and casting of lots, they pay attention beyond any other people. Their method of casting lots is a simple one: they cut a branch from a fruit-bearing tree and divide it into small pieces which they mark with certain distinctive signs and scatter at random onto a white cloth. Then, the priest of the community if the lots are consulted publicly, or the father of the family if it is done privately, after invoking the gods and with eyes raised to heaven, picks up three pieces, one at a time, and interprets them according to the signs previously marked upon them." ~Tacitus
Runes are an oracle from which one seeks advice. They work best if you detail your current circumstances and then ask a specific question. Rune readings are sometimes obscure. They hint toward answers, but you have to figure out the details. This is when the rune casters intuition becomes paramount. Some times the Runes "sing" to me, and their meaning becomes instantly clear.
Runic divination or "rune casting" is not "fortunetelling" in the sense that one actually sees the future. Instead, runes give one a means of analyzing the path that one is on and a likely outcome. The future is not fixed. It changes with everything one does. If one does not like the prediction, one can always change paths!