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