prepare solution - sodium hydroxide solution (Jan/17/2011 )

How should I prepare 0,02N sodium hydroxide solution to receive the exact concentration? Maybe I should standardize it? Then how to do this?

I learned to standardise it by titration with an acid of known concentration, e.g. HCl. The acid needs to be standardised too of course with a substance one can weigh very exactly (e.g. potassium hydrogen phthalate). Easier is it of course to buy a solution with certificated concentration or to titrate the base with oxalic acid, which you can weigh also very exactly.
Out of the volumes, concentrations you can calculate the exact concentration of the base, as you know the stoichiometrical relationships of the reaction.

thanks )