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