Get the basic concepts cleared first. By basic I don't want to say that you don't know JS.
Learn Closures - why they are helpful, how and when they can be used.
Mutation & Centralized states - why & when they are needed ( I'm not focusing on Redux or any pre-built tool , lets focus on the concept and implement it yourself in JQuery or plain javascript or Angular -- Your code will look a lot more clean & readable. )
Read others Js code, Read Npm modules , Checkout few open-source projects etc.
Checkout Javascript Ninja Videos ( They are very helpful in making you industry standard JavaScript developer )
Subscribe to Javascript topic on Medium , You will be continuously reading awesome JavaScript articles.