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