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