Are you living in a state where you are able to pay in state tuition? I live in California, so I was lucky that paying for school was not as expensive. for 12 units I paid roughly $300 and about $360 for 15 units. This was back when tuition for community colleges was $20 a unit. However, during my last semester it more than doubled to $44 a unit, so I paid about $570 for a 12 unit load. Now that I am at a CSU, tuition is about $3700, which I only have to pay $800 thanks to financial aid.
Anyway. The most important element that helped me pay for tuition and other living expenses was living with my parents. They did not require me to pay rent, food, or any utilities so as long as I went to school and paid for it on my own. This was definitely a good trade off for me.
As for work. I would average about 20-22 hours through the school semester and during the summer breaks I would do anything from the same 20-22 hours up to 40. The key to saving up for college and other living expenses is to be very cautious of how you spend your money. For example, I am a big coffee addict, so I would spend about $20 on coffee a week, that is about $80 a month and $1040 a year. After I brought this crazy expense in my life, I started to make my own coffee and I would treat myself to coffee once a week, or I got myself to just drink straight black coffee which only cost $1 at McDonalds.
Paying for college is definitely doable. You just need to come up with a game plan and do your best to stick to it. If you can stay disciplined, you can definitely accomplish it