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