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