Post, delete your post, then post again. That way you don't add "bumping power" to the topic.
(This only works on boards with a "bump" button)
I think this is nice to the op question. Because when I saw the topic and read through the content I was about to say that there is no way one can reply to thread he has created without bumping. So with this your "delete and reposting" method is also good. But there are some boards, the author can't delete his own post and when report to moderator before it can be deleted and not all topics moderators are deleting.
And if the moderator has not deleted the post can I move the thread to archive and recreate the topic to bump it again?