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