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