Communicating to users/clients is hard... specially if they are not that knowledgable about software developement. so here's a list of things that i think could help you to better communicate with people.

Be sensitive about their knowledge about the subject matter and bring yourself to the same level as they are into. Being on the same page makes it easier for you and the people you are talking to to receive and understand what you are talking about.

Try not to use too much computer jargons, they might think that you are an alien or a super sonic geek talking gibbrish. Remember! not all people understand computer terms. Also, you can use descriptive words when talking about technology although too much low-level descriptions might also distrupt the message.

Answer their questions. Most of the time they would like to know what you mean and that they are willing to learn what you are trying to say so be willing to answer any questions. Answering questions helps you communicate to them better.

And lastly, Be calm. Dont show to them that you are getting pissed because they cant understand what a wesite is or if they think recursion is a way of unwinding in the summer(see this). After all, its you who wants to do bussiness with them :)