How can you neutralize an aqua-regia solution using sodium hydroxide solution?

First dilute A.R. by pooring it SLOWLY into a large amount (10-fold) of (cold) water while mixing, and then (SO AFTER dilution) the same (molar) amount of NaOH (diluted) can be poored into it in the same way.

This careful procedure is required because of high reaction heat and aggressive chemicals and toxic fumes might escape when not done carefully.