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