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