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