The Casting Spreads in this Guidebook are modern, and so is almost all rune divination practised today. That is worth knowing, not a reason to stop. This page sets out what the historical record actually says, and where the modern methods came from.
Around 98 CE the Roman historian Tacitus described the Germanic peoples in his Germania. Chapter 10 is the passage every rune book cites:
Auspicia sortesque ut qui maxime observant: sortium consuetudo simplex. Virgam frugiferae arbori decisam in surculos amputant eosque notis quibusdam discretos super candidam vestem temere ac fortuito spargunt. Mox, si publice consultetur, sacerdos civitatis, sin privatim, ipse pater familiae, precatus deos caelumque suspiciens ter singulos tollit, sublatos secundum impressam ante notam interpretatur. Si prohibuerunt, nulla de eadem re in eundem diem consultatio; sin permissum, auspiciorum adhuc fides exigitur.
Augury and divination by lot no people practise more diligently. The use of the lots is simple. A little bough is lopped off a fruit-bearing tree, and cut into small pieces; these are distinguished by certain marks, and thrown carelessly and at random over a white garment. In public questions the priest of the particular state, in private the father of the family, invokes the gods, and, with his eyes towards heaven, takes up each piece three times, and finds in them a meaning according to the mark previously impressed on them. If they prove unfavourable, there is no further consultation that day about the matter; if they sanction it, the confirmation of augury is still required.
Latin: Tacitus, Germania 10. English: tr. Church and Brodribb (1876), public domain. The phrase ter singulos tollit is read either as "takes up three, one at a time" (the usual modern reading) or as "takes up each piece three times" (as here).
Medieval poems and sagas are full of rune magic: victory runes carved on a sword-hilt, runes on a drinking-horn against poison, runes miscarved on whalebone that make a girl ill. None of them describes reading the future from runes. The Eddic poem Völuspá says the three Norns, whose names are often read as past, present, and future, "scored on wood" as they set the fates of men; that image, not any recorded rite, lies behind the modern Nornic spread. The nearest thing to runic divination in the whole medieval record is a late stick from Bergen (1375 to 1400) that conjures Óðinn, called there the greatest among devils, to name a thief.
None of this makes the spreads less useful. It makes them modern, and now you know whose.
— Evander Blackwood