Woozy Woo there are 2 hard parts to this. 1 is making the decision in the 1st place which you've done so you're half way through! The 2nd is to actually go through with it.
There is a lot to do in a house move and dividing things up is a further complicating factor. When it's all in front of you it seems like a mountain. But a good place to start is to take a pen and paper and write down each thing that will need to be done, don't try and get them in the right order, you can do that later, just start writing a list, always keep a pen and paper in your pocket for the next couple of weeks because more and more things will pop in your head to add to the list which you don't want to forget. Once you think you have a completed list, re order it. You can then start to work towards each stage 1 at a time so that every one become little humps rather than a big mountain all together.
speaking from experience it is absolutely of the highest importance that you are as clear and honest with your partner about what is happening, why and what is going to happen.
If you don't love him any more and don't want to be with him any more and are moving out and moving on then SAY IT. DO NOT say it's not you it's me, I need to find myself, I don't know why but I feel I've got to go, I don't think this will work etc...... If you KNOW what you're doing then leave him in no doubt. Say: I don't love you any more, I don't want to be with you any more, I am going to move out and start a new life. I know this is what I must do. I can not stay any longer. Thank you for what we had, but we don't have it any more, I feel we can/can not be friends.... I intend to keep/not keep in contact..... etc.
DO NOT leave the guy wondering if this is some crisis you're going through and will one day return when you have realised you can't live without him. If you truly don't want to hurt him, then you will have to say thinngs kind of bluntly so that it goes in and he can heal healthily from the break.
Sorry for the pep but this is a subject close to my heart.!!
Most of all, if you know you have a brighter future then remember to stay focussed on it and enjoy the prospect of it. If it has all gone wrong it will feel and will be a release to enjoy and look forward to. IT will be difficult but you have such a lovely future ahead of you.