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