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