1) Community College
The average cost of a 2-year, in-state college is a little over $3,200, compared to $8,800 for a public 4-year school. Certain community college courses can satisfy credit requirements for 4-year colleges if you plan to transfer, meaning you can take the classes for a lot less. Make sure to double check so that you don't wind up with credits that don't transfer over, causing you to re-take similar courses!
2) In-State vs. Out-Of-State Colleges
That $8,800 for an in-state school jumps to $22,000 for out-of-state schools.
3) Financial Aid
In order to qualify for federal financial aid, you must fill out FAFSA forms (https://fafsa.ed.gov/) every year before the deadline. Also, make sure you're strategic about scholarships. Do extensive searches for scholarship foundations and non-traditional organizations that will offer scholarship money.