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