Based on the awesome Oceanic Next by Dmitri Voronianski
Download the repo
Open Terminal go to Preferences and choose the Profiles tab
Click the cog at the bottom of the profiles list and import oceanic-next.terminal from the download file
Select oceanic-next from the list of profiles and hit Default to make it...you guessed it...the default profile
Adjust to your preferred font if necessary
Restart Terminal
In the screenshots I am using SF Mono Light @ 14pt with line spacing bumped to 1.1