In GitLab, you can easily tag issues and merge requests. If you have permission level `Developer` or higher, you can manage labels. To create, edit or delete a label, go to a project and then to `Issues` and then `Labels`.
Here you can create a new label.
![new label](labels/label1.png)
You can choose to set a color.
![label color](labels/label2.png)
If you want to change an existing label, press edit next to the listed label.
You will be presented with the same form as when creating a new label.