Move (or "Undo") last git commit to unstaged area [duplicate]
Solution 1:
You can use git reset to set the current branch to the preceding commit, i.e. HEAD^
git reset HEAD^
Adding --soft will keep those files in the index: (ready to be committed)
git reset --soft HEAD^
--soft(…) This leaves all your changed files "Changes to be committed", as git status would put it.
Solution 2:
git-extras provides a git undo command which is an easier to remember way of doing the same thing (along with a number of other handy extras, as the name implies).