In Latin culture to have a horn means your wife is having fun with someone else. The horn is a visible trophy of your inability to handle your own wife or a sign that you have a bad wife. In any circumstance to possess a horn not is a good thing.
To help those with horns to help identify themselves, I have written this instructable.
Readers feel free to send this paper to someone you know to inform him that his wife has other interests. You may want to deliver and run as he might come after you with his horn or more importantly feel free to send this instructable to someone who doesn't have the need but want improve his "Horn Technical Culture" and would like to know HOW TO PUT HORNS ON HIS CAR.