To create a custom page, you will first need to access your blog dashboard.
Then, click on "Pages", and then "Add New", from your Dashboard menu on the left.
This page will look incredibly similar to the "New Post" page, but it is for creating a "New Page". Pages are used more often for static information, such as an About Me, biography, or a contact page.
Blog posts, in contrast, are considered to be time-oriented components.
Design your page how you would like to, set all the settings you would like to set, and "Publish" the page when you are done with it.
Now, when you go back to Pages → All Pages, you will see that your published page appears.
Note: Pages are not automatically added to your menu that appears on your blog. An extra step is needed to add the page to one of your menus, if you choose to do this. Please see the Knowledebase article titled "How Do I Add A Page to My Menu?"