Things To Do First

Functions

Contents by Categories: Find the documents in the community by the relevant categories.
Connect with Others: Follow the organizer and other community members to receive their new activity updates. Create a personal network.
Calendar: Check the project calendar to see the latest schedule and deadlines for certain tasks.
Communications: See replies to your posts, blogs, etc. (A number appears on your Communications in the top menu bar alerting you)
Activity: Activity shows the full activity stream throughout the community, filtered the way you want it, including key content recommendations from C4D Administrator.
Direct Messages and Private Discussion: Limit your audience to only the people you want.
Rate or Like Content: Rate or like content so others know it's useful.
Bookmarks: Keep track of your favorite content inside and outside of TDD CoP.
@Mentions: Alert people, places and groups that you're talking about them.

For basic functions of C4D, you may also want to have a quick look at: Collaboration for Development Basics