Search and read. "Cycles" have been explained. Including in the spreadsheet.
Since the third glyph slot for Combat is pretty flexible, I've been thinking of using Glyph of Slice and Dice, which the spreadsheet shows as a very minor downgrade from Glyph of Eviscerate (-6.5 DPS).
I'm unsure of what rotation to use, however. Back in the TBC days (with the T4 bonus that gave the same amount of extra SnD), I remember you could do stuff like 1pt SnD, 5pt Eviscerate, repeat. Are there better cycles than that now?