One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,6)(3,7,8,5)(9,10,13,16)(11,14,17,21)(12,19,20,15)(18,24,23,22)(25,26)(27,37)(28,34)(29,36)(30,32)(31,35)(33,39)(38,51)(40,50)(41,49)(42,46)(43,48)(44,45)(47,54)(52,55)(53,56)(1,3)(2,5)(4,8)(6,7)(11,17)(12,20)(14,21)(15,19)(26,32)(33,45)(34,46)(35,36)(37,50)(47,55)(48,49)(51,56) involution — undirected(9,11)(10,14)(12,18)(13,17)(15,22)(16,21)(19,24)(20,23)(25,27,30,40)(26,33,32,45)(28,38,42,53)(29,39,31,44)(34,47,46,55)(35,37,36,50)(41,52,43,54)(48,56,49,51)(3,8)(5,7)(11,17)(14,21)(18,23)(22,24)(25,28)(26,34)(27,38)(29,43)(30,42)(31,41)(32,46)(33,47)(35,49)(36,48)(37,51)(39,54)(40,53)(44,52)(45,55)(50,56) involution — undirected(9,12,13,20)(10,15,16,19)(11,18,17,23)(14,22,21,24)(25,29,30,31)(26,35,32,36)(27,39,40,44)(28,41,42,43)(33,37,45,50)(34,48,46,49)(38,52,53,54)(47,56,55,51)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.