What is the best path to becoming a rock start front end web developer?

Practice!

There are many resources online to help learn and practice your web dev skills. Udacity has a great course that's pretty comprehensive and free. There are also sites that allow you to host a website for free where you can develop yourself. The Udacity course shows you how to use Google App Engine to create your own website. I would definitely recommend going through that course and afterwards come up with a website idea of your own and build it! Note that the course is an intermediate level, so if you're new to programming you may want to check out the prerequisite courses (also free!) first.

Great choice of career! There's always lots of demand for rock star front end web developers.

Aside from the other answers here, I would say time, practice, and patience are the most important things to have. It takes time because you need to learn to code, and learn what makes good (and bad) web sites. The best way to practice is to intern with or get a job with a digital agency or web development company. Finally, patience: it won't happen overnight, but if you set your mind to it and keep at it, you can do it!

The first step to becoming a rock star frontend developer is to become a rock star developer in general. Javascript will likely be your primary program language (assuming you're talking about web development), but learning any particular language is secondary to the core skills which all good developers share. You need to understand algorithms, common patterns, best practices, http/network behaviour and optimization and at least the basics of the full stack as well as the obvious front-end technologies. Finally, the single most important (and most underrated) skill for any developer is communication. You need to not only be able to communicate with other developers, but also product and business partners and customers.

For individuals new to both programming and the front end, I recommend a mixture of classes (whether at university/college, through a bootcamp or various self-learning options) which lead to a well-rounded understanding (not just a crash course in the frontend). Along with this, lots of practical experience - dissect frontends which interest you or do things you don't understand, develop personal projects (sites/apps/whatever) and read everything you can get your hands on. Finally, once you know enough to be dangerous, find an open source project you personally use and try submit improvements to it. The sooner you have professional programmers reviewing your code and giving you feedback on it, the better.

If you have more specific questions about being a frontend developer for the web, I'd be happy to try and answer them.