Hi {{first_name}},
[[personalized comment]]
I’m writing to you because I’m interested in contributing a guest post on your site.
Based on what has worked for [[Site name]] in the past, I feel that your readers would love these ideas:
[[Idea Title & Brief Description] ]
To give you an idea of my writing style and quality, here’s a guest post I recently wrote for [[guest post link]]
Do you think these ideas would be a good fit for your [[site, publication, newsletter]]?
Best,
[[your name and title]]