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