How do I repost?
First, view your old post on the site. You can find your old post by going to the Your Posts page and clicking on the title of the post that you want to repost.
Once you are viewing your post, you should see a button or link labelled "Repost" below the post title if enough time has passed since the first time you made the post (different groups have different restrictions on how often you can repost). Once you click the repost button, it will automatically fill in the new post form with the correct information and then you just have to click the Submit button.
Alternatively, you can simply fill out and submit the new post form manually. The repost button just saves you some time.