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