If it helps your workflow any, ctrl+n,ctrl+s will create a new file and prompt you for a name as a quick 2-key combination.
Alternately you can set up a custom key binding to invoke both commands in a chain to make it a single keypress:
    { "keys": ["ctrl+shift+n"], "command": "chain",
      "args": {
        "commands": [
            ["new_file"], ["save"]
        ]
      }
    },
Using of course whatever key you want. However ctrl+n to create a new file and ctrl+s to save are common to a lot of software, so  it may be worth getting in that habit so your workflow can move with you as you go from software to software.