At the beginning when you start Celtx its splash page appears and to start a project you should click on a template from the heading project templates, after this you can start your scriptwriting.
After this has been completed you can add things to your project like the script or storyboard etc, by clicking on the add button at the top left corner.
To use Celtx services an account should be made by clicking on create an account and following the instructions. Once this is done your projects can be uploaded.
To save projects just go onto file and save project. However if you want to delete a project find the file and just simply delete it.
Note-To use Celtx you may have to download it!