How do I start to pare down on eliminating 2/3 of my paper collections and memorabilia?

I am 75 yrs old. Given 10 more years of reasonable health, what are these collections for? They jog my memories of people, travels, places and events. So it’s like my brain. I would like to move into a small retirement apartment – out of a 5 bedroom house. I think I’d be like all or nothing. What kind of strategies can you suggest? – for dealing with incoming papers as well as long-stored collections.