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