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