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