One of the big projects I have on right now is a Shopify based shop for a client who sells hand made baby clothes, crystals and other related items. She was in fact the impetus for my HTML5 Boilerplate for Shopify site. My client, and she won't mind me describing her as this as she's an old friend - is terrified of computers. Where I spend 8-10 hours a day directly online, and never further than 5 feet from a connected device, she checks her email once a week. Where I use a top of the range Macbook Pro linked to a 27inch screen, she has a basic version of Windows 7 on a 12inch sub notebook. Our experience of computers & the internet is totally and utterly different.
Learning to empathise with your clients is essential, it's the same skill you should be using to empathise with the users of the sites that you create. Presuming the same level, or even a similar level of technical experience and know how will lead to disaster. I have worked in many a team where we trot out the old "Users are stupid" line. But it's not true is it? They aren't "stupid" they just aren't as knowledgable in our field as we are. It is our job as good designers, as good UX creators to think how other people feel and to design to fit them not to fit us.
Why did I mention this client? Well - she had to copy a lot of data into Shopify when she started adding her products. Shopify does have a CSV upload option but given the technical nature of the upload - we decided to go with the straight web interface instead. When we did the training to show her how to insert copy, well let's just say even I was surprised.
Apparently the best thing I have taught her so far is that CMD-C copies whatever you selected, CMD-V pastes it and CMD-Z is a magic undo. She's now very very happy.
Do not treat your clients or users as stupid, they are not. They are just not you. We spend our lives so deep inside Twitter, or Facebook or Tumblr or any one of a dozen other places, we have smart phones, iPads, Kindels and the sort of technology that ten years ago would have looked like magic, most people do not.
Be kind, be understanding, do not get frustrated. lacking experience is not stupidity.