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