One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,6)(3,7,8,5)(9,10,13,15)(11,14,17,21)(12,19,20,16)(18,24,23,22)(25,26)(27,35)(28,32)(29,42)(30,33)(31,38)(34,43)(36,49)(37,50)(39,54)(40,47)(41,56)(44,52)(45,53)(46,55)(48,51)(9,11)(10,14)(12,18)(13,17)(15,21)(16,22)(19,24)(20,23)(25,27,29,38,30,37,43,53)(26,31,34,35,33,45,42,50)(28,39,41,55,40,36,51,52)(32,46,48,54,47,44,56,49)(1,3,4,8)(2,5,6,7)(10,15)(11,17)(16,19)(18,23)(25,28,30,40)(26,32,33,47)(27,36,37,39)(29,41,43,51)(31,44,45,46)(34,48,42,56)(35,49,50,54)(38,52,53,55)(11,17)(14,21)(18,23)(22,24)(27,37)(28,40)(31,45)(32,47)(35,50)(38,53)(41,51)(48,56) involution — undirected(9,12,13,20)(10,16,15,19)(11,18,17,23)(14,22,21,24)(26,33)(31,45)(32,47)(34,42)(35,50)(44,46)(48,56)(49,54)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.