Below are the steps we could follow to change the look of a SharePoint 2013 site:
- From the Site Settings action menu, click the Change the Look link.
- From the Change the Look page, select a site design.
- Upon selecting a design, click the Try It Out button.
- On the design preview page, click the Yes, Keep It button.
- And finally, we have already changed the look of our SharePoint 2013 site.