To delete comments you've made on a post in a pod:
On the discussion post you'd like to delete your comment on, click on the icon shown below.
Then all the comments on that discussion will pop out, similar to what's shown below.
On only your comments in the discussion you will see the four options 'Like, Reply, Edit, Delete' like shown below, click on 'Delete'.
To Restore Your Deleted Comments
Just click on 'Restore' under your deleted comment, easy as that!