There are a few ways I've gathered testimonials over the years - one is to recognize a great snippet when a client emails you ecstatic about your finished project. Email the client back and say 'you wrote X. Y, Z... I'd love to use this as an official testimonial - would you mind? I'd like to include your name and company name, and possibly a link back to your site if I use it on my own website. Any thoughts?'
Or, just ask for one!

Try something like this 'Client X, I'd love to be able to include a testimonial or statement from you about our work together these past X months in the new brochure/website/marketing whatnot I'm creating for my company. It could be about a particular project I completed for you or just a general overview of your opinion of my work ethic, business standards, etc. Your quote would be followed by your name and company name, and a link to your website if used online. Thanks so much for your consideration! I appreciate you as a client and am looking forward to your feedback...' [I just wrote this so if it's too wordy, or needs editing by all means pick it apart so it sounds like your own voice

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