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