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