Appreciate your summers and use them wisely. Don’t let the system brainwash you into thinking that you need to do something this summer to get that internship next summer, which will lead to that other internship and then That Job. Travel to Japan or Patagonia, write a book, read, spend time with family, learn a new language or skill, follow things that interest you, that cliché but wise voice in your heart.
I was/am a nontraditional student (about five to seven years older than most students at my university), so this was not quite in my realm, but I was often jealous of the many opportunities afforded to these students. Yes, you have to go to social events. Yes, you might get categorized as a snob or fill-in-the-inappropriate-name-blank, but you really can benefit from the social network and resources (such as old tests).