It depends on what level do you want to attain in graphics designing field. If you are a creative mind then this platform is very much meant for you. If you are planning on some simple jobs like designing flyers, business cards, some websites and like stuff, then it is not necessary to go to a design school and get a degree. There are plenty of resources available on the internet today that will sufficiently help you to groom yourself into a graphics designer. Moreover, any career requires self-directed study, the most. However, if you want to have a robust career in this industry, then having a degree from an affiliated institute will definitely give you an edge. Graphic designing is not just an art, it requires a firm knowledge base on theory, technology, craft, communication, business, typography, besides having an artistic flair. It is not about self-expression, it is about communication in visual form - it is about making a profit to your client and solving their problems satisfactorily. And as things are evolving at a rapid pace in today's society, you will always need to upgrade and add to your skills, else, the danger of being left behind is quite real. Obviously, a degree will not guarantee you a job but it can improve your chances. At the same time, it is equally true that one can secure a job in this industry without a degree but with a killer portfolio.  It is just rare but not impossible that an individual can do it on his/her own.