These steps assume you have already connected your Twitter account with Please Share. If you have not completed this step, you can learn how to do so here.
When you select the Reply button associated with a tweet that appears in Slack, this action will enable you to comment on the tweet on Twitter. A text box will appear in Slack where you can add a comment and submit it to Twitter by selecting the green Reply button.
Upon doing so, you will receive a confirmation message in Slack and your reply will be added to the tweet on Twitter a few seconds later.