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