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