Specifically papers. Personal papers you don't want to keep.
It's hard for most of us, and we're all different, but here's what's working for me.
I am easily overwhelmed but I want the job done. They weigh on me these thoughts from my past. They served their purpose, but that was then and this is now and they don't spark joy they just give me an uneasy feeling every time I look at them. I motivate myself by looking at blogs and videos (there are millions of them, including mine!) I remind myself that I have rarely if ever regretted getting rid of stuff. I look around at the areas I have cleared and feel the calm spaciousness. I also remind myself that it is highly unlikely that anyone else would ever want to, or have the time to, wade through them. I won't be leaving them to my old university either :-)
I consider just burning the lot, but I am too curious about what I've written....
Sometimes I start with a quick first pass getting rid of the obvious throw-aways. That reduces the pile. Good. Then I might do one of several things. I tell myself I will stop as soon as I feel overwhelmed (I've just done that with a drawer of cards which have been sent to me - very emotional.) I will go back to it another time.
Or I commit to dealing with the first 2/5/10 sheets, read them, decide keep or shred and put them in the keep folder or shred them straight away. I know I may go through the keep folder again at some point but as the aim is to reduce the pile I try not to put 'maybe' ones in there. I get some momentum going and begin to enjoy it.
Or I set a timer for 15 minutes and tell myself I am allowed to stop when it goes, or keep going if I feel like it. I often do keep going - it's the starting that's the hardest.
I've been 'Kondoing' since I first came across Marie Kondo's book in 2014. i knew that her tender animism towards objects combined with a kind of ruthlessness or clarity of purpose was for me and it's worked well for me. The loft and the basement are clear. Yay! The bags of shredded paper go into the compost bins. A friend who took a welding course when she was seventy and has been making sculptures ever since, took away a box of old tools from the shed yesterday. An art teacher is taking a big bag of surplus paper and materials. The old lanterns have gone to the charity shop since I bought the lovely new ones, and a feeling of lightness is coming over me, and a spark of - is it excitement? - is stirring somewhere deep within...
Find out what works for you and go for it!