Simply. Softly.
That's how I approach a clutter bust with a client. I show up quiet on the inside. I focus on my breath and let my mind float. The client is often nervous. I let them be. I often think of something I like about the space and say it. I get a feeling for the space underneath all the stuff. The space likes to be complimented.
Then I sit down in my client's least favorite part of their living space with trash bags and begin. I know they are going to be okay. I know they are going to feel better as they begin to see what they no longer need and decide on their own to let it go. Helping people to again rely on their intuitive promptings is the best thing I can do for them.
I think you can approach your own clutter situations the same way. All of the previous anguish, and "Why did I let it get this bad," and stuckness, can sit and stay in the past. You find a spot and you start. You can sit on the floor, or in a chair, or stand. It doesn't matter. You pick the first item and you consider it. "Hmmmm. Do I like this? Am I using it? Do I love it? Would I buy it if I were in a store today?" You're considering the item from who you are now. What do you like and what fits you now.
I remember one of my first clients. We were working in her kitchen. I didn't have a game plan. I looked around and saw her cook books and thought to ask if she used them to cook meals. She said all but one of the cook books were gifts. She only used the one she bought for herself. Since she wasn't using the gift cook books, I thought to ask her if she'd be okay letting them go. She thought about it and said yes. We packed up the gift cook books in bags which I later dropped off at the library.
My client felt good letting go of something that wasn't serving her. You'll feel the same way as you consider what's in your space and let go of what doesn't fit.