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