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)(16,17)(18,27)(19,21)(20,23)(24,28)(25,26) involution — undirected(5,6,9,10)(7,8,12,11)(13,15)(14,20)(16,23)(17,26)(18,28)(19,25)(21,24)(22,27)(1,2,3,4)(5,7)(6,11)(8,10)(9,12)(13,16,19,18)(14,17,21,27)(15,23,25,28)(20,26,24,22)(6,10)(7,12)(13,17,19,27)(14,16,21,18)(15,24,25,20)(22,28,26,23)(5,8,9,11)(6,7,10,12)(13,16,19,18)(14,17,21,27)(15,23,25,28)(20,26,24,22)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.