double subs

OK I am putting 1 x Hertz 12 inch HX 300D SVC No I am thinking of whether to do 1 x sealed Box and 1 x ported Box .....? or 1 x double 12 in ported ...? or 1 x double 12 in Ported ,,,,,,? Up facing ...? front facing ....? Rear facing ....? where can I get plans ??? the 2 x 12s will...