When I find I am not motivated to begin a project, I first spend a few minutes thinking what is the first thing that needs to be done if I were to start. No matter how small a task it is, that is where I start, and I will do whatever is necessary to accomplish it.
For example: I needed to go through three years of legal papers, receipts, tax stuff, a huge, mixed bag. It accumulated due to an illness from which I recovered. It all needed to be looked at and either filed away or discarded.
After thinking about it, I realized I needed a file box and file folders; an indelible pen to label them and a highlighter to call out dates on forms; and a stapler. I took a ride to the stationary store and bought everything except file folders. Those I knew I had and after a 10 minute search in my back room, I found them. I also got out the shredder while I was up there.
I made a project out of just setting up. It was something I did not mind doing. But once I had everything I needed, shredder, trash can, recycle bin, file boxes, blank files, the copier, the stapler, marking pens, I was able to start. I set everything up in front of the TV, tuned in to the ball game, and opened the first shoe box of receipts. After identifying the item it represented, I created a file for that subject, stuck the receipt in it, stuck the file in the file box, and picked out the second slip of paper. Suddenly, I was on a roll, and finished this enormous job in two weeks.
In summary, my suggestion is, break the job down into smaller, easy to accomplish tasks.
Read Quote of Nathan Ketsdever's answer to Motivation: How can I motivate myself to work hard? on Quora