A couple of days ago, in the middle of the Rush Limbaugh brouhaha, I leveled a lazy broadside at the old windbag and his unconvincing apology. Did I score any points? Well…he’s a big target. And it was a bad apology.

On Monday, Limbaugh kept up the apologizing on his radio show–and, in my opinion, dug himself a deeper hole.

Regardless of whether you’re a Dittohead or a Rush hater–or you simply don’t care–there’s an art to making an effective public apology, and it’s something every marketer should know. In this day and age of 24/7 media chatter, you never know when someone associated with your brand is going to say something dumb.

So, using Rush as an example, here are six thing you shouldn’t do:

1. Don’t address the person you wronged. Limbaugh never actually addressed his apology to Sandra Fluke, the person he said awful things about. Both in his written apology and on his radio show, he tells the world he apologizes–but he never uses language that addresses his victim directly. The world heard the slander, so the world needs to hear the apology–but your primary audience should be the person who got hurt.

2. Fail to make a complete apology. Rush apologized for calling Sandra Fluke a “slut” and a “prostitute.” But he left a lot of other things unaddressed. He said she wanted the government to pay her to have sex, and he said he wanted her to upload videos of her having sex to the Internet so he could watch. These were just as awful as the name-calling, but Rush ignored them. A half-apology makes the whole thing seem defensive and false.

3. Blame someone else for your wrongdoing. On his radio show, Rush said that his mistake was sinking to the level of his rivals; essentially, “the liberals say awful things about people all the time, and I just did what they do.” Even if it’s true, an apology is not the time to bring it up. Because it’s irrelevant to the apology. Your wrongdoing is not about what anyone else did: it’s about the bad thing you did. When you rationalize your wrongdoing based on someone else’s bad behavior, you come off looking like a defensive jerk.

4. Don’t say “I’m sorry.” This is a pretty easy one. Rush never actually said, “I’m sorry.” “I apologize” is not the same thing–it’s a cold description of your intention, not an expression of how you feel. If you don’t say “I’m sorry,” it isn’t really an apology at all.

5. Keep lying. Rush said he didn’t mean a personal attack on Ms. Fluke. That, quite simply, is a lie. He did mean a personal attack; the things he said were personal. Better to say, “I attacked you personally, and I’m sorry” than to say he didn’t mean to do. He attacked her for three days, for crying out loud. If you lie in your apology, the whole thing seems disingenuous.

6. Try to time your apology to have the least media impact. Rush apologized late on Saturday afternoon, when almost no one would be paying attention. At least, that’s the conventional wisdom. But in today’s overheated social media environment, everybody’s paying attention all the time. In fact, the timing worked against him; Rush’s sorry-ass apology was picked up quickly and used against him on the Sunday morning political talk shows. He’d have been better-off if he’d waited until his show on Monday to make a heartfelt, direct apology.

Take responsibility. Be direct. Express genuine sorrow to the person you wronged. It’s not the difficult. And remember that the public really does have a pretty short memory; much as some of us would like to believe otherwise, Rush is probably going to be just fine.

But the way he apologized certainly didn’t win him any new fans. Rush missed an opportunity to prove that he’s a big man. Er, bigger man. You know what we mean.