I find it helpful to think about a work day in terms of tangible objects as opposed to hours spent. And within that, identifying a big project that you absolutely must get done that day is a helpful practice. There's a book called "The One Thing" that is helpful in thinking about this.
I have an unlimited gym subscription and go there almost every day. On weekdays, it has really helped me build discipline. I also make an effort to dress up nearly every day and work from quiet cafés, usually in 4-hour sessions, and 4 hours from home!
Understand what is behind your procrastination, usually it’s not the task itself but fear of failure, distractions or not finding any meaning in the task