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