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