Windows Terminal is a new, modern, fast, efficient, powerful, and productive terminal application for users of command-line tools and shells like Command Prompt, PowerShell, and WSL. Its main features include multiple tabs, Unicode and UTF-8 character support, a GPU accelerated text rendering engine, and custom themes, styles, and configurations. Here are some links that might be useful for you:

• Introducing Windows Terminal
• Windows Terminal Build 2019 FAQ
• Windows Terminal Microsoft Store Preview Release

Currently the  preview release can be found from the Windows Store but if you like adventures, checkout this GitHub repository.

To customize the new windows terminal open settings by Pressing ctrl + , or open it from dropdown situated on right of add tab “+” button. This should open a json file named profiles.json in your editor of choice. I’d recommend using an editor like VS-Code but plane Notepad is also fine for the job.

If by any means your are not able to find your profile.json file, have a look inside %USERPROFILE%\AppData\Local\Packages\Microsoft.WindowsTerminal_8wekyb3d8bbwe\RoamingState

{
    "globals" : {...},      //Dictionary containing configuration options like key bindings and buffer size.
    "profiles" : [...],     //An array containing profiles for each shell. it can also contain multiple profiles for same shell.
    "schemes" : [...]          //Array containing all color schemes.
}

To create an new profile, you have to open a Powershell terminal and generate new GUID by typing the below cmdlet.

PS C:\Users\tzman> New-Guid

Guid
----
94dfbd4d-3f99-4971-8b32-ab3ca19acdd1

then add a new profile in profiles.json

{
    "globals" : {...},
    "profiles" :
    [
        {...},
        {...},
        {...},      //existing profiles
        {           //very basic new profile
            "closeOnExit" : true,
            "commandline" : "powershell.exe",   //replace this with "cmd.exe" or "wsl.exe -d <distribution_name>"
            "guid" : "{79285a8e-036c-446f-8a9c-78994e34bf78}",  //paste here the guid you created earlier enclosed in curly braces
            "colorScheme" : "Campbell",
            "icon" : "https://upload.wikimedia.org/wikipedia/commons/2/2f/PowerShell_5.0_icon.png",     //local icon path or URL to your icon
            "name" : "PowerShell custom profile",
            "startingDirectory" : "%USERPROFILE%"
        }
    ],
    "schemes" : [...]
}

TIP : you can set this profile as default by copying it’s GUID inside "defaultProfile" attribute of "global" dictionary.More attributes of “profiles”Acrylic Background

• useAcrylic – Boolean
  toggle’s Windows style translucent background
• acrylicOpacity – Floating point value b/w 0 and 1
  (1 : Totally opaque)
• background – Hex color code
  default : “#000000”

Background Image

NOTE : You need to disable acrylic to enable these properties

• backgroundImage – String
  link or path to your .png or .gif
• backgroundImageOpacity – Floating point value b/w 0 and 1
  (1 : Totally opaque)
• backgroundImageStretchMode – String
  Fill/Fit/Stretch/Tile/Center/Span

Font

• fontFace – String
  Font name
• fontSize – Integer

Cursor

• cursorColor – Hex color code
  default : “#000000”
• cursorShape – String
  filledBox/bar/emptyBox/underScore/vintage
• cursorHeight – Integer