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