The first 3 questions go to you: Who? What? To Whom?

A target group is more than a statistical construct. Target groups are made of people.
Imagine one of these individuals. Formulate your core message for this person.

Most probably you could easily write a whole book about what you have to offer. Say it in one sentence, or two as a maximum. That's how you capture the core of your message.

And last but not least:

From whom comes the message? The sender  needs a clear identity. The product needs one as well. Do you have a good name for it? Is it clear what this name is standing for  ?
Does your communication reflect the identity?

When all of this is clear, we go  on...>