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