  We uncover a method of calculation that proceeds at every step without fixing
the gauge or specifying details of the regularisation scheme. Results are
obtained by iterated use of integration by parts and gauge invariance
identities. Calculations can be performed almost entirely diagrammatically. The
method is formulated within the framework of an exact renormalisation group for
QED. We demonstrate the technique with a calculation of the one-loop beta
function, achieving a manifestly universal result, and without gauge fixing.
