I've been slowly getting better at decluttering and the Kondo book was very inspiring to me. This year one of my NY's resolutions was to put out AT LEAST one bag when a local charity does a pick up on my street. It's September and I've kept my resolution so far. But, the thing that gets me is making sure that donations go to the right place and it slows me down, as well. I have multiple bags in the garage for different places things go and it was making the garage cluttered! A few months ago, I gave up and just set everything out for the charity that does the pick up. It still makes me feel sort of bad and I wish I had the bandwidth the get the "good/expensive" things to places/people who I know could really use them. For now, I just have to be satisfied that it is out of my house.
ETA: More than decluttering, though, the single biggest thing that has helped is that I've just stopped buying things that we don't actually NEED. I've stopped being tempted by a good deal on things that just add more 'stuff' in our home or on 'too good to pass up prices' on anything. That shift in mindset, for me, has been huge. Of course, our house could still use a lot of decluttering!