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