Do you remember the silly paper clip in Microsoft (or how about the puppy?), that would appear after you opened Word and started typing? Look’s like you’re typing a letter… If you were, the formatting prompts were helpful. If not, they were an annoyance but it was Microsoft’s way of recognizing you and walking you through best uses of their software.
Your online community should do the same (in a much less annoying way). Whether you create a video introduction for your new members or welcome them with an email and a suggested activity, make sure you tell them where to start. We are all too busy to just kick around on a site. When you direct their actions, you’re ensured they see and experience what you want them to immediately instead of stumbling across it weeks later. You have their attention now. Use it to direct them to something they will enjoy and they’ll keep coming back.