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