1. State your goalThis means to make a plan. We are talking about chance encounters of anywhere from 30 seconds to a few minutes. How do you plan for that? You know the opportunity will occur and recur. So, think about what you will say if you meet someone you want to impress. Start by identifying your unique value proposition. You are not "just" a lawyer. You have areas of competence. You have a way to resolve client problems. You have experience dealing with certain issues. Use a few sentences to describe your model client, what you will do for that client and what makes you different. With this, you know who should hire you and why. That is a good start.
2. Explain yourself
Whatever your goal, express it by replacing "I am a lawyer working with XYZ" with your value proposition. Perhaps, "I help real estate clients through their transactions painlessly." Or, "I enable family law clients achieve win-win solutions". Think it through. Why would someone retain you? Yes, include your firm name. But that is not the selling proposition. You are.
3. State your proposition
When you explained yourself (above), you made the introduction. Now, sell yourself. How do you do what you claim? Express your technique in a few sentences. It can be difficult to shorten a business model to a couple of sentences. Figure out how to do it. Then practice in front of a mirror. Practice on your friends. Practice on your colleagues. Record your pitch on your cellphone and listen to it. Carefully. Ask for feedback. Whatever it takes, make it simple. Make it heartfelt. Make it effective. You say that you are a lawyer? Well, persuade.
4. Show your personality
This is not easy in a 30 second presentation between the third and fifth floors of the court house. Use simple language, short sentences, speak slowly, and look your interlocutor in the eyes (don't stare!) That is about as good as it gets.
5. End on a high note
This really means to end on a note that encourages further engagement. You might hand over your business card, but that rarely convinces anyone. Better, you should ask for their business card. Take a moment to study it. Really care about what you are reading. Make a comment about it. And bonus- it helps you remember their name.
Then, follow up with a (handwritten?) note that has your contact information and a link to your web presence. I am not a fan of using a "call to action" in an elevator speech. Meet, present and then follow up later. That is the formula. You cannot close the deal in a couple of minutes. All you can do is open the door to a further interaction.
6. Be consistent
There is no sixth point in the Edward Jones blog post. But there should be one. Make sure that your web presence is consistent with your elevator pitch. For example, don't stress a pit-bull reputation on your website and sweetness in your elevator pitch. Don't stress your informal attitude in person, and show a serious black business suit on your website. Be consistent.
Many elevator speech opportunities occur at cocktail parties. For tips about how to handle yourself there, check out Eugene Meehan's blog post here.
For more tips and techniques about professionalism, check out the podcast interviews at Chat with Lawyers.