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