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