I was in the same situation for more than four years. The only reason I stayed for so long was at the time my career wasn't very important to me -- my main focu

I was in the same situation for more than four years. The only reason I stayed for so long was at the time my career wasn't very important to me -- my main focus was my band, and even though it was infuriating, my horrible job afforded me the time and money to be able to focus on music. When the time came for me to think about moving on, I did a few different things. First off, I went to udemy.com and brushed up on my framework skills. At the time I was a front end developer, so I too courses in jQuery and Angular.js, then took a refresher course in Java. From there I started doing volunteer development work for local non-profits so I could round out my portfolio. After that, my job hunt was pretty easy. All-in-all my ramp up took about 6 months or so, and it lead to me getting a job that I love.