Testimonials help to create belief.
I have asked several thousand workshop attendees about them.
They respond by telling me that testimonials work in their businesses.
Testimonials are more believable than you writing about how great you are.
Ask customers to give you written feedback via email.
Display the nice things that they say about you, wherever you can.
Have a separate web page for testimonials.
Use them in newsletters, business cards, proposals, adverts and printed matter.
Testimonials are a form of social proof.
Some customers may not be keen for you use their names.
If that is the case, you could attribute a B2B testimonial to (something like): ‘Director from the construction industry’ or ‘a customer from London’ in the case of B2C marketing.
Final thought: remind customers that you appreciate testimonials, within your email signature.