Sometimes we find ourselves fully concentrated in a design that a minimum distraction can make you lose the thread of what you were doing.
There's an easy way to quickly switch from a design to another inside a project, all in the same context.
Click on the arrow icon next to the design's name you're currently working on, this is located at the top left corner of the screen.
A menu containing all the designs in the project will drop down. You can re-order them, filter them by tags or search for a design.