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