Provide a clear example of a similar job you have done in the past.
I've worked with a science and research company which had a website built with wordpress and as the policies didn't allow to use public plugins, I had to create everything from scratch and build my own plugins.
Proposal:
Hello,
My name is Bruno, I've been working for over 4 years on the web development industry and I am now starting my freelancer business on this website.
I've worked with small brands, store owners to major brands like Minipreco, Sana Hotels and some others.
I would be honored to help you build your business online.
I hope you chose me.
Best regards,
Bruno