How do people get out of low pay “unskilled” jobs into good jobs?

I'm in retail and have been here for the last 8 months, I really need to get out since I'm stuck at a dead-end job, low pay, and pretty bad coworkers/manager. I can't stay here for much longer since I feel that the longer I wait, the harder it will be to get out. I really don't want to do college as I feel I would just be paying for a degree, I'm sure I could self study any topic online more efficiently then what college would do. A lot faster then 4 years