Now promise yourself that after x amount of time or pages, you get the reward. You can try this with any distasteful task, but be sure to break the task into segments. After x minutes of cleaning or x paragraphs of writing, you get a treat.
This works in part because the brain has a reward center, which I’ve usually seen referred to as the nucleus accumbens, that helps you focus on anticipation of reward. (Enjoying the pleasure takes place in an entirely different part of the brain.) Dopamine is released, and besides being a pleasure neurotransmitter, it’s a pay-attention neurotransmitter. In a perverse twist, these two things get hijacked in drug addiction, playing a part in incentivizing very destructive behavior.
Some people can make self-incentivizing work by promising themselves a big reward, like a new sweater, once the whole job is completed. However, my students have reported that it’s most effective when you break the job into smaller pieces and use smaller rewards.