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