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