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