happy- wat zman said.
are you on stock 19's? if so, a clean look at stock height is 15mm bolt-replacement type spacers front and rear. some folks like 10mm on the rear.
for a more aggressive look people use 20mm all around... or if lowered 20mm/25mm bolt-on spacer setup.
so you got:
ET47 (stock) - 15mm stud replacement spacers = ET32 for front
ET30 (stock) - 15mm stud replacement or bolt-on spacers= ET15 for rear
hope this helps.