In JIRA connected with STASH you can create a feature branch for an issue using the button \'create branch\'. (That is nice to track the commits in this issue.)
If a dev
As for january 2017 if you have an already exiting branch and you want to attach it to a Jira Issue you can do the following:
Execute the following command
git branch -m JIRA_ISSUE_ID-Whatever
Assuming that mine Jira issue is SO-01
I can do the following:
git branch -m SO-01-Whatever
This will change the name locally, push it to remote with:
git push origin :old_name
git branch (-m | -M) []
Related question for more info