Personal projects are helpful. Identify a problem you have that you want to solve (using whatever medium you want to work in professionally, Im in software design atm as an example so id make an app), identify other people with the same problem, learn about the problem from them, explore solutions, test them, iterate, go to market. Document the process along the way for your portfolio. Use that experience to get gigs on toptal/angellist/upwork/etc which you should document for your portfolio. 6mo later get a job at a startup/agency.
If you want help kickstarting this with a solid product design process Id recommend this free coursera course: https://www.coursera.org/learn/design