In my memoir Almost 5'4" I share many of my early modeling mistakes and how I overcame them in hopes you won't make them, also I wrote a lot about the hands-on work I put in to get ahead. The designers I approached, the magazines I submitted to, and how I approached professional photographers with concepts and landed my first tearsheets in magazines on my own.
A lot of girls tell me about the trials of being a model, especially when they are short.
With the Internet becoming such a big part of our daily lives it tends to be the place a girl first goes to learn about modeling and market herself as one. However, the Internet is no place to start a modeling goal, modeling happens when you are modeling "something" -a product-and there are many aspiring brands out there you could contact and approach about modeling for their advertising, especially now when budgets are lower for brand marketing.
Use Google to research brands and small companies, go to tradeshows, craft fairs, boutiques, bring a headshot or compcard. Don't rely on the Internet for you to be discovered, it doesn't happen like that. There is no short-cut, you have to do the work. Try jewelery designers, handbag designers, scarfs, hats, shoes, these are good to consider, especially because there is no height requirement to model a handbag!
These days aspiring brands might need a model but can't afford a high fashion agency model. So that is your cue to get on the ball and market yourself in bigger ways, towards a goal, and with a brand.
With no experience you might not get paid a ton at the start but it is better to get quality experience than waste time counting hits and comments because modeling happens when you "model something". Don't let your height hold you down, and don't settle, aim higher, chase more, want more for your goals.
Also, having some experience, showing the agency you can model, that you have done it before, that you have worked with a brand, aspiring or established, will give you a better chance to be welcomed to work with the agency, despite your height.