pick a room, maybe the bathroom because it is small. Clean it but if you feel overwhelmed, take a break, visit Hubpages then in 10 minutes go back to it. In no time at all the bathroom will be clean and tidy and the process has begun.
Day 2, pick a room or if that is too much, pick a corner, glean, toss, pack in boxes, whatever it takes --if you cannot bring yourself to get rid of things, you may have a more serious problem called hoarding.
If you keep up this process on a daily basis, in a week or so, you house will be clean-then you can relax and just maintain it.
If you have older kids not living at home, make sure they take all of the things that belong to them out of your home. /If you have kids at home, enlist their help. Have them spiff up their rooms and make it organized.
Ask your spouse, boyfriend or best friend for help, tell them you are overwhelmed and need assistance, and be willing to let things go that you do not display or use. I have done this recently, finally realizing that keepsakes packed in the garage in boxes are of now use to me or anyone. Keep a few things and take pictures of others and let stuff go. It is a wonderful feeling.