Setting up the Sidebar and Footer
Let’s start with the sidebar - the sidebar is generally used to display different widgets and used as an area to briefly promote / introduce yourself to your readers. The sidebar can sit on the right or left hand side of your blog and can also be visible on posts and pages. You also have the choice of removing the sidebar from individual posts and pages, this is within the post / page editor in the Post / Page Options meta box.
To add widgets to the sidebar, go to Appearance > Widgets and drag and drop the widgets you require into the Sidebar widget area. These widgets will now appear in your sidebar on your blog pages, however you can also mix and match widgets to go on your page sidebar too (if applicable). To add widgets to your page sidebar, drag and drop them into the Page Sidebar widget area.
If your theme has widgets areas for the footer, you can add widgets to this too. Like the sidebar, drag and drop your desired widgets into the three footer column widget areas. The Instagram feed will appear when you add the Instagram widget into the Instagram (Footer) widget area via Appearance > Widgets.