You do it already. You spend a portion of your research hours on the here and now, a slice or two on what's to come, and a sliver on the past. What you may not do is purposefully work out what the best balance is between past, present, and future. To preclude a nighttime visit from a hooded Ghost of Projects Yet to Come, a la Dickens, take some time to analyze your present allocation.
If you define present projects as everything from bench work to publication, then future projects include brainstorming, networking, and fundraising. Past projects would be time spent archiving samples and data. Before you say "Bah, humbug!" think about it as balancing your short-term and long-term goals with a dose of housekeeping to boot. Time management on a macro scale.
Unlike other time-management strategies, this one doesn't require a day planner. The pie you divide into past, ...