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