Satisfy The Audience In Your Head
As a member of an audience you don't like to wait, do you? The longer you have to wait, the more anxious you get about the start of the performance.
You have an audience inside your head-it is called the pituitary gland and hypothalamus. They are waiting to send out cheers called endorphins when you accomplish something of value to you. The longer you wait to perform a difficult task, the longer you deny the audience the chance to give you much needed applause.
For that reason, consider accomplishing the task you are most dreading earlier in the day. That way, you have this audience clapping and cheering you on all day long.