Get a mascot/logo
A programming language will only be as popular as its mascot is cute.
In all seriousness, having a good logo/mascot is quite important. Preferably it would be a parrot of some kind (because of the name "Inko"), and something that can fit on a shirt or be made into a plush. I absolutely suck at logo/brand design, so we'll need to find somebody else to take care of this.
Go is a good example. Say what you will about the language, but the mascot stands out and it's easy to make (sometimes questionable) variations of it:
Edited by Yorick Peterse