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