One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(6,8)(9,10)(11,19)(12,22)(13,16)(14,20)(15,17)(18,23)(21,24)(25,26,30,29)(27,31,35,33)(28,36,38,32)(34,40,37,39)(3,7)(6,8)(9,11,15,13)(10,16,17,19)(12,20,23,21)(14,22,24,18)(25,26,30,29)(27,33,35,31)(28,32,38,36)(34,40,37,39)(1,2,5,4)(3,6,7,8)(10,17)(14,24)(16,19)(18,22)(26,29)(31,33)(32,36)(39,40)(1,3,5,7)(2,6,4,8)(9,12,15,23)(10,18,17,22)(11,21,13,20)(14,16,24,19)(25,27)(26,31)(28,37)(29,33)(30,35)(32,40)(34,38)(36,39)(1,4,5,2)(3,8,7,6)(9,13,15,11)(10,19,17,16)(12,21,23,20)(14,18,24,22)(25,28,30,38)(26,32,29,36)(27,34,35,37)(31,39,33,40)(9,14,15,24)(10,20,17,21)(11,22,13,18)(12,16,23,19)(25,29,30,26)(27,33,35,31)(28,36,38,32)(34,40,37,39)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.