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