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