$ git checkout -b <new branch>

Commit any local changes then:

$ git push -u origin <new branch>

$ git branch -D <branchName>
Deleted branch <branchName> (was ....).

$ git push origin --delete <branchName>
To git@github.com:<repository>.git
 - [deleted]         <branchName>

Merge branch into current branch

$ git merge <branch>