Networking is essential when considering graduate studies. I met my research advisor at an informal chemistry meet-up in Brass Taps two years prior to working for him. You'll never know when opportunities present themselves, so it's important to take chances and meet everyone you can.
I advise prospective grad students to network with as many interesting people as possible. Networking is key to finding research opportunities and gaining experiences. Even simple conversations can stimulate new ideas or help solidify original ones.
Graduate school is an incredibly enriching experience. Focusing on what interests you most brings a whole new level of richness to your learning. In addition to your courses there are also opportunities to refine presenting skills, attend conferences, and work as a teaching assistant for undergraduate courses which blends education and work experience together to prepare you for a fulfilling career.
Get involved in the community. Grad school is more than your research project; expand your contributions beyond your field of research and into the community where you are working.