When putting together an email campaign, imagine your reader as the sun that the email and all it's elements revolve around. 

Rather than putting yourself at the centre and trying to express how much of an expert you are, how you are better than the rest; try to see it from the readers point of view. This should begin right from the subject line, because remember: subject line is make or break. Imagine yourself as the reader and ask yourself: would I want to open this email? What would be in it for me? Why are they sending me this? What will I gain? Then, write your email from that perspective.