First thing you offer
Say what it is and what the visitor gets from it, in plain words.
A clear promise in one line
One or two sentences that say what you do, for whom, and why they should care.
Second thing you offer
Keep each of these to two or three lines: people skim.
Third thing you offer
Three is enough for a first page. More belongs on its own page.
A reason to trust you
How long you have been doing this, who you work with, or what makes you different.