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