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