There are a lot of ways to promote an ICO project but as I know the most effective way to do it is advertising. You can rent the advertisement place in this forum or on the coinmarketcap.com. Beside you can run the advertise about your project on Facebook or Youtube as well, it's also working. Moreover you can try to ask some trusted member in this forum to manage your ICO bounty campaign, it's also help people believe in your ICO project when the bounty campaign managed by a trusted manager in here.