Pick one room. (I'd suggest the smallest room you have)
Work ONLY in that room for the day or until you finish it. That's how I managed to get my kitchen done.
I started one room at a time, 1 drawer or cubbard at a time. I take everything out (or almost everything) clean the space and then put it back and discard everything that I no longer want or need.
I also make myself as comfortable as I can while I do it so that I don't tired too quickly...
My house is feeling so much different already... the more I get rid of and declutter the more I find the things I need, have place forthe things that didn't have a place before etc... it also makes it so that it is so much easier to keep clean!
if I can do it... you can too!!!