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