Chat
When starting a chat, right click on the other person's body and press Homepage. This will bring you to their page and show the profile. It gives you some idea of who you are talking to, age, location, etc. Of course it may not be true, but at least you have some idea of what the person wants to be seen as.
Avatar
Initially you are assigned a grey image as your profile avatar, it also shows up on chat request. It's boring and does not make you look good. To change it, take a snapshot of yourself. From messenger, open up a 3D window, change to a room that you like. If you do not want a room showing, choose the Bionic White Room. Choose the clothing you want, the mood, etc. At the bottom right of the chat window is Take snapshot, press it. Use the mouse to move around and position yourself, and wait for the random movements of your avatar to be "just right", then take the snapshot and Upload as avatar