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