Fill your profile. Use your real name - otherwise no one will be able to recognise you in the service.
Create a private channel with your name clearly shown. Your friends will be able to see it, and can write to that channel to talk to you. You can use the channel to post short messages of what you are up to (microblogging), or longer ones if you like. You can also create public channels - but beware: they are visible to all Ossi users.
Check the list of groups and join those that seem interesting. This gives you access to their channels and the profiles of the posters. Invite some to become your friends. Post. Create a group of your own with a theme of current interest to you.
Update your status often. Be creative.
Still no friends in the service? Ask your friends to join it! The more the merrier.
We plan to introduce further means to stay in contact with your friends in the future - stay tuned!