What is your most effective room-by-room downsizing strategy for a smaller apartment

[GaryNL]

I'm preparing to move into a significantly smaller apartment next month, and I need to drastically downsize a decade's worth of accumulated belongings, from books and clothes to sentimental items and old electronics. The sheer volume is paralyzing, and I keep getting stuck on how to decide what to keep. For people who have successfully navigated a major downsizing, what was your most effective strategy for tackling the process room by room without getting overwhelmed, and how did you handle the emotional difficulty of letting go of items that have memories attached but no practical use?