User blog comment:SusM/Argh!!! Screw you Gigginox, Cha-cha, Me(Wha...?)!!!/@comment-10592682-20130711100658

A decoration won't give you a effect straight away. They will help you rack up points in that particular category. If you get enough points (you can check the nessicary amount under the equipment or status menu) the effect will be granted to you. Charms and Armour skills will also help you collect points.

If I remember correctly, 10 points under the poison catergory will get you half poison, and 15 will get you null poison. That's what you want to aim for. Be warned though: -10 points will get you double poison.

Hope this helped.