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