1. To post a reply to an existing thread, first click on the forum category if you're not already there and then click on the thread title of the thread you want to reply to. Then just scroll down to the bottom of the list of current replies until you see the Editor box:
2. Enter your reply and click on the "Post Reply" button at the lower right.

2. Enter your reply and click on the "Post Reply" button at the lower right.