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