Here is a quick tutorial about how to create a new post in forums.
For the purpose of tutorial, lets say you want to start a new topic in "Seismic Design". See the attached images as they explain detail about posting.
Step 1: Click "Seismic Design" Forum from main index.
Step 2: Click on "Start New Topic" Button on top right corner.
Step 3: Fill out the required fields as explained in the attached image.
That is it!
Should you have any questions about posting, please ask below.
Many Thanks!