  The Catani--Seymour dipole subtraction is a general and powerful procedure to
calculate the QCD next-to-leading order corrections for collider observables.
We clearly define a practical algorithm to use the dipole subtraction. The
algorithm is called the Dipole splitting algorithm (DSA). The DSA is applied to
an arbitrary process by following well defined steps. The subtraction terms
created by the DSA can be summarized in a compact form by tables. We present a
template for the summary tables. One advantage of the DSA is to allow a
straightforward algorithm to prove the consistency relation of all the
subtraction terms. The proof algorithm is presented in the subsequent article.
We demonstrate the DSA in two collider processes, $pp \to \mu^{-}\mu^{+}$ and
$2\,jets$. Further as a confirmation of the DSA it is shown that the analytical
results obtained by the DSA at the Drell-Yan process exactly agree with the
well known results obtained by the traditional method.
