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