The goal of this document is to describe the important practical aspects in
the use of an Equivalent Width (EW) method for the derivation of spectroscopic
stellar parameters. A general description of the fundamental steps composing
any EW method is given, together with possible differences that may be found in
different methods used in the literature. Then ARES+MOOG is then used as an
example where each step of the method is described in detail. A special focus
is given for the specific steps of this method, namely the use of a
differential analysis to define the atomic data for the adopted line list, the
automatic EW determinations, and the way to find the best parameters at the end
of the procedure. Finally, a practical tutorial is given, where we focus on
simple exercises useful to illustrate and explain the dependence of the
abundances with the assumed stellar parameters. The interdependences are
described and a clear procedure is given to find the "final" stellar
parameters.Comment: 15 pages, 4 figures, accepted for publication as a chapter in
"Determination of Atmospheric Parameters of B, A, F and G Type Stars",
Springer (2014), eds. E. Niemczura, B. Smalley, W. Pyc