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