Communicate your core value proposition in 5-6 words. This is usually the first thing visitors will read and is important for Google quality scores and Adwords. If you need more words to explain your value proposition, use a sub-heading
to get into the detail, and use the heading for a summary or teaser. I have attached an example from Stripe.
Bullet out 3 advantages of using your product or service. Think benefits and not features. When Steve Jobs introduced the original iPod, "1000 songs in your pocket" was much better messaging than a "5 GB hard drive". The style you
communicate with here should resonate with your brand. I've picked out an example from Mailchimp.