Take care of the visual first.

Most rooms have  visible clutter and hidden clutter:
The pile on the chair and the mess in the drawer.
The stacks on the desk and the chaos in the file cabinet.
The accumulation on the counter and the disarray in pantry.
The collection of random on the bookshelf and the mysteries in the cabinet.

First sort, prioritize and organize what you can see. 
Then deal with the items in the unseen spaces.
By starting with what’s out and visible;
with the clutter you see on a daily basis,
you can see change immediately.

The situation then feels less overwhelming,
the distraction level has been greatly reduced
and you can start to concentrate on the next level of clutter.

Some of what you declutter in the visual spaces
will need to find homes in the hidden spaces, so
the opportunity to decide how best to use your storage spaces
becomes more obvious. 

Plus, by starting with what you can see
when you get inside of the other places you will 
be practiced at decision making!

Start with one area of visual clutter.
One shelf, one area of counter top, one table top.
Feel and see (literally) what a difference that can make.