All options and customizations offered by the Hubble theme are available at WordPress Customizer which is placed at Dashboard>Appearance > Customize menu. Theme specific settings are available in Theme settings section.
Logo or your personal photo. Note that you should upload a square photo or logo there.
Retina Logo which will be replaced by the logo when visitors use a retina deisplay device like.
The name that will be displayed under the logo
The title that will be displayed under the logo
By default WordPress shows recent posts in homepage and also has the capability of setting a static page as homepage.
You may want to set a page as your homepage rather than you posts list. This can be done in Dashboard->appearance->Customize->Static Front Page :
From Customizer > Theme Settings > Social icons you can add as many social icons as you want.
Add new item
Select the social media from the dropdown
Insert your Profile Url
Repeat this for other icons
You can choose from various google fonts for the headings and the body texts of your theme.
You may need to have additional sidebars. Sidebar is a widget container that you can add some widgets to it using admin panel and then place it where possible at the blog sidebar or inside your pages using the visual composer.