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