You have 2 options to create a new design: you can either start from a template or a blank design, adding element by element.
Creating a design
Use the Create button from the top-right corner to create a new design and select one of the preset sizes or create a custom size.
After you select the size, you can use a template or start from a blank design.
The left bar menu is where you find all the design elements you need. 
Background
Here you can choose a background for your design. The available options are:
- Colors
- Gradients
- Textures
- Images
Text
Each design needs some text. You can choose from 3 default textboxes or text templates.
Add your own files
You can do this in the tab My uploads - you can add images, videos, audio files, SVGs, or GIFs.
Buttons
You can choose from any existing buttons and edit them as needed. 
Elements
On this tab, you can add various elements such as:
- Brand logos and elements
- Stock Photos, Videos, or Audio
- Shapes
- Masks
- Lines
- Icons
- Illustrations
- Logos
- GIPHY - GIF Library
- Widgets - YouTube Video or Embed code
Magic animator
With this feature, you can quickly and easily animate your whole design. Give them a try! :)
Templates
Even if you started from scratch, you could still select a template - be it static, animated, or video.
Brand kit
This is the place from where you can change your Brand Kit. It will automatically change the fonts with the ones you set up on your brand kit, along with the colors and logos.
Note*: You can also find the logos in Elements-Brand Logos, and your colors will be available everywhere where you can choose a color under the Primary palette.