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