Just as important as getting traffic is converting it and retaining it, track your conversion statistics along each step of the way, find your major pitfalls an

Just as important as getting traffic is converting it and retaining it, track your conversion statistics along each step of the way, find your major pitfalls and fix them. Split users randomly so they see different landing pages for example and track the changes in conversion. This will improve your virality as only active users spread the word.