Microsoft SharePoint is an effective tool for your business management. Creation of new master page is one of the added feature of SharePoint.

1. How to create a new master page in SharePoint 2013?
Microsoft SharePoint 2013 has proven itself as a collaborative environment
that allows the various business organization to optimize their efficiency
irrespective of their size. Here we will discuss on one of the most frequently
asked questions from the SharePoint 2013 user beginners. Yes, you got it right!
We will be talking about the creation of a new master page in SharePoint 2013.
Planning
A master page represents the core element of your website. These are those
elements that remain constant from page to page. This will require the fonts,
images and analytic to be present on each page. The content in the middle of
the page can be managed by SharePoint using a combo of page layout and
dynamic content. Before moving on to the SharePoint it is advised that you
should make a trial HTML version with the core element isolated.
Creating an account
Creating a Microsoft account for sign up is the first step you should take in
order to create a new master page. You also have the option to download the
SharePoint beta version locally.
Publishing site creation

2. Once you have created an account, you are provided with a public facing and a
collaborative site. Now you have the option of either going with the public
facing view or making changes to create own publishing site collection. The
latter is recommended as Microsoft allows only one public site in the current
cloud environment. To create a new publish site go to
Admin>SharePoint>site collections>and then click on the new private site
collection.
Mapping master page directory

3. After the completion of the above step, you will be left with a new publishing
site with customization to be made with your master page. Now you have to
click on Design Manager so as to progress with the further processing. Click on
edit Master Page.
After that click on HTML to SharePoint conversion button, a dialogue box will
appear. The directory is the folder showing the master page and layouts along
with their dependent assets.
Go to windows explorer, right click and select map network drive. Copy and
then paste the URL for the location of this directory and put your login
credentials.
You will get a drive letter that maps to this folder and you can copy paste the
files from your local machine to SharePoint directly. In case you are unable to
map the drive, you can upload the file through UI by going to site settings and
clicking on Master pages and page layout.

4. Creating a Master Page
After uploading files, we will create a new SharePoint Master page. SharePoint
directly converts HTML files into ASP.NET Master Page automatically.While
doing so it will sync the changes to Master Page. Now go to Design Manager,
click on edit master page and then click on convert HTML file to SharePoint
Master Page. Select HTML file and click insert.
Publishing Master Page
This is the last step in the process. To publish go to site settings>Master pages
and pages layout, and look for your HTML layout and then find your HTML
file. Now click on publish button. Assigning Master Page to your website
To assign the master page on your website go to site setting>Master page and
then select your master page from the drop down list. After this, your site will
adopt to the new look and feel.
Finally it is done
After following all the steps, your website will adopt the new master page
created through SharePoint. You can now utilize it to maximize the working
efficiency of your business and make changes from time to time.