I was once quoted a speed declutter tip, which did actually work.
Putting a charity bag in each room, then going round each room individually and putting in the bag anything that you didn't use or find beautiful. Then putting each bag in a corner of that room till you had a moment to go through it.
When I first sat down to go through a bag I could easily see what had to go to the bin or charity, and I was left with things I'd actually just bought, which made me try them out, rather than immediately sticking them in a cupboard and forgetting about them.
It breaks down the declutter process into more manageable chunks I found.
I've nearly finished decluttering my house, but I'll use this to do another sweep as I've left tapes, music, books and paperwork, which really needs to be gone through, to decide if I really still want them.
By sweeping them into one container in each room, I can have my shelves/cupboards as I want them immediately, and then I can go through the bag in my own time.
This tip doesn't work if you have a helpful relative/friend, who decides to take your charity bag to the shop without asking you first!!!