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