1) Find a patsy. Someone, involved in something criminal, like some petty theif involved in drugs. I'm sure we all have friends like that.
2) Tear a small piece of it off.
3) Pay the person money to write in the book for you. Make sure they don't know you too well. Tell them if you keep their secret, they'll keep your secret.
4) Have them write my name in the book 4 times, misspelled. Tell them my name is spelled like "this" instead of "that", when "that" is my real name. This can also be used to prove that it can't hurt anyone.
5) If they ever rat you out, or you think they will, write their name on the small scrap and make their death condition involve returning the deathnote to you before they go elsewhere in the city and step out in front of a semi.
6) Test to see if conditionalities can be executed like a programming language to allow the person to die immediately if the person is "guilty" or die in their original time and manner if they are "innocent". Use it on people who are already going to die, who already deserve it. Do your homework.
7) If the note can be used conditionally, then use it to punish people guilty of crimes against humanity that are above the law. If not, then look for some other method of absolutely determining guilt or innocence.
8) If the heat comes on, kill the patsy through an accident, return the note, and stop. Make the trail run cold. Lock it away and don't use it until your normal life causes you to have to move, change location, and legal jurisdictions.
9) If you're a direct suspect, frame someone else. Even if you have to write them into the death note, leave them with a fake copy, and create "witchcraft" trappings and obvious ceremonies.