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