It is never too early to start writing out your resume. In fact it would be beneficial to start one sooner than later. All of your past jobs, volunteer work, activities, and leadership positions can be put into it. The longer you wait the harder it will be to remember all of the things you have done over the years. Upon graduation all college students will need to have one made. By starting it now or as a freshman you can put down as much as you have and add to it later. It will  be less time consuming by sitting down once a semester and updating it compared to trying to write the whole thing at once the semester before graduation. It will also give students a chance to think about things like volunterring and work experience before the last minute. It will allow more time for those activities, instead of only a semester of volunteer work you could have four years worth. It doesn't have to be in perfect format, but it would be beneficial to start a resume now.