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