lewpuls "Intentions" post has inspired me to share some thoughts on practical techniques for meeting deadlines. I will try to get some basic thoughts and examples down with the hope that some good discussion will start...
1) Commit to the deadline. If you aren't taking the deadline seriously yourself, there is very little chance of meeting it on time. If a deadline is proposed to you that you know is unreasonable, try to renegotiate the deadline immediately rather than waiting until the last minute to request an extension. If you are successful (and I think there is a good chance that you will be), make sure you hit the new deadline.
2) "Back into" the deadline. What does that mean? In my experience, there are many steps required to meet a deadline and I find it helpful to "back into" the deadline date. For example, a publisher asks that your prototype be delivered in 90 days. It will take 5 days to travel by mail (85), 1 day to package and confirm you have included all parts (84), 2 weeks to receive all of the game components (70), 1 week to print (63), 1 month to playtest and review feedback (33) leaving you with slightly more than 1 month design, develop and test the game before playtesting.
3) Hope for the best, expect the worst. The above example assumes there are no problems along the way. Will holiday shipping increase the mailing time? Is your printer backlogged with orders and unable to finish in 1 week? Is your game component supplier out of dice? Try to give yourself extra days to allow for unexpected delays (down to 25 now...) and develop a back up plan as early as possible.
4) Communicate clearly and often. Whenever you are dependent on another person or company to help you meet a deadline, you should be very clear about your expectations at the start of the project. The people assisting you will appreciate knowing the requirements at the beginning rather than needing to change direction mid-way through the project. For example, if you need cards printed, be clear with the printer on the size of the print job and when it is needed.
"I need 6, 52 card, 4 color decks printed with the attached image on the back, cut, boxed, wrapped and delivered to me to later than November 20th. Can you meet that requirement?"
And then follow up with a phone call or email! It would be nice if everyone told you about new problems that are delaying your print job, but don't expect that. In this example, I would expect that a professional printer would not mind a follow up call a few days later to ensure there are no questions or missing requirements. Later, you may speak or email again to ensure your print job is in progress and finally to ensure that the job is finished and shipped.
If you leave the impression that you are serious and "on top" of the project, the people helping you will be more likely to be "on top" of their responsibilities. If you leave the impression that the deadline is not important, then you can expect that your project may be delayed in favor of a more "serious" deadline.
Hopefully this helps - I would love to hear anyone else's advice for meeting deadlines!