I agree that research internships and/or a job at an engineering firm who be very smart steps towards building a strong resume when you are ready to start your career. In terms of the kinds of experiences to seek out in college, my suggestion to you is to keep an open mind. If there is a particular field of study, a specific class, or a specific professor or teacher's assistant that you get a good feeling about, you may consider seeking a work opportunity in those spaces. It may be in the form of a job (getting knowledge and getting paid) or volunteer (getting knowledge with pay to come later :)). In either case, experience (different types and types that build on one another) will be very important during your college journey.
Another thing that I hope you find helpful...engineers have a reputation for being all computation and no personal skills. That is an over exaggeration of sorts...but...I do recommend that you expose yourself to experiences where you build and strengthen your communication skills, specifically how you verbally interact with others. Strong communication skills and experiences that help you build them will also be an effective asset in your career building journey.
Best of luck to you!