There is a simple rule of getting things done and that is to do what you like the least first. Following that logic, I make all of my prospecting calls first thing in the morning. If I try and do them after lunch or at the end of the day, I‘m tempted to give a million and one reasons why I am not able to make the calls until the next day.  I agree: tele-prospecting stinks, but you have to do it.  Getting it done first thing in the day helps a lot.