Yesterday was a busy day for me. I had to take our doggie out for 2 walks (which is a real challenge at the moment due to the weather!)
And I had to help clean house, help prepare dinner, etc.
One little thing I do, when I'm anticipating a difficult task or day, is I visualize myself doing something pleasurable I will be doing after my difficult task or day has been concluded. It might be something as simple as watching a TV program or sitting on the couch in front of the fireplace with my laptop replying to posts here on PC. I visualize myself doing that & feeling the satisfaction of having accomplished whatever difficult task(s) I had to do.
Then later in the day, when I have actually completed my difficult task(s) & I'm doing whatever pleasurable thing I thought about earlier in the day (or perhaps even the day before) I think back to how I thought about this before my difficult task or day began & I say to myself: "Wow, I thought about being here doing this before my difficult day began & now here I am!"
Somehow this little trick always seems to help get me through.