To edit a project, make sure you are logged into your account. Next, scroll down on the dashboard page and on the left hand side of the screen you will see an area titled: article requested. Along with a "view" button. Click the view button. This will take you to a page listing all of your projects. Click the "+" icon located next to the project you would like to edit. This will expand your project details. Next, click the "edit project details" link. You will then be able to edit your project. You will also be able to retract a keyword or project by clicking on the retract project or retract keyword link. This will remove the project OR keyword from the queue.
Note, this option will not be available if a writer has already started writing your project. If a writer is currently writing your project, there is a chance that they only started to write and may cancel out of your project after the displayed timer ends. In this case, you would then be able to retract your project or keywords OR edit your project.