  I formulate in a colour-friendly way the FKS method for the computation of
QCD cross sections at the next-to-leading order accuracy. This is achieved
through the definition of subtraction terms for squared matrix elements,
constructed with single colour-dressed or pairs of colour-ordered amplitudes.
The latter approach relies on the use of colour flows, is exact to all orders
in $N$, and is thus particularly suited to being organized as a systematic
expansion in 1/N.
