Keep a running spreadsheet of all valuable professional contacts as you go through college, and life honestly. Include their name, company, title, contact info, when you last spoke and something personal to remember them by. When you are out there looking for internships and jobs, this list will be your saving grace because these professionals already know you. Save yourself the stress of going into an internship cold and use the pre-existing connections you have.
Another great personal spreadsheet to keep is all past events or major projects you've worked on. This is a good tool for pre-interview prep. You can review all of your achievements so you are ready to talk yourself up and back up those promises with facts and experience. This also helps when you are building/tweaking your resume.
This is a little different because the type of spreadsheet completely depends on where you work. At the bare minimum I recommend keeping track of reach-out because it doesn't look good to send the same Introduction email twice. Make sure you keep helpful databases of potential clients/bloggers/segments/topics - so this way if you lose track of time (which we all do once in awhile) you have somewhere to pull from easily.
My best advice is to just stay organized and up-to-date. That way you look professional and have way less stress on those sumer tanned shoulders.
Happy Updating. xoxo