PSA: Have a company blog? Link to your company site.
Just a reminder for all of you with a company blog: Make sure you put a prominent link to your company's main website.
It worked well for me in the past, with several signups tracked back to the blog.
Reduce friction at every step. Yes, making me guess/search/type in your website address is friction.
(I'm looking at you, http://blog.mailgun.net/, but it's just the most recent example I came across.)