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