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