Getting Started with Google Sites
1. Open your browser and navigate to sites.google.com.
2. Choose a Site template from the Template Gallery or click on the Blank plus icon to start with a blank Site.
3. Starting with a template, provides preset themes, elements, and content that can be built upon and customized.
4. In the Sites workspace, the main menu side bar on the right, is where users can customize their Site by selecting themes, adding pages, and inserting various elements to enhance their Site.
5. The Pages tab will show all of the pages that are included in the Site. Add or delete pages on your site by clicking the plus button at the bottom of the Pages tab and then click New Page. You can easily change the order of the pages by clicking on a page in the menu and dragging up or down. Dropping a page into another page will nest the dropped page under the other. Click the three dot icon on a page in the menu to change that page to your homepage, duplicate, delete, or manage its properties. 
6. Google Sites has many preset themes that can be applied to change the look and feel of your site. You can also import or create custom themes. To customize a theme, click the three dot icon in the top right corner of the custom theme box. Then click on Edit.
7. Opening edit will allow you to change the colors, styles, text options, logo, image header, navigation settings, the look of components, and apply these settings to your entire site.
8. The Insert tab is how you will add content like text, images, video, and other elements to your Site. Using the Insert tab, select an element like table of contents, image carousel, button, etc. Elements can be moved around the page by dragging and dropping. The blue line will show you where the element can be dropped.
9. Use the Preview button to see how your Site will look on a computer, tablet, and mobile device.
10. When you are ready to publish your Site, click the Publish button. You will be able to modify the web address and change permissions to manage who can view your site. 
Resources
For more information on using Google Sites visit How to Use Google Sites - Tutorial for Beginners (Video).
Discover an extensive collection of Google Sites How-to Videos by visiting LinkedIn Learning and logging in with your App State credentials.
Browse Google Help Articles detailing How to Use Google Sites.