You managed to get started, now how to keep going?

Seinfeld method

Jerry Seinfeld once described his method for making better jokes: work on it every day. His system is to have a wall calendar and mark an X on it for every day that he put effort into writing his jokes. After getting a chain of X marks in the calendar, you are motivated by not wanting to break the chain. GitHub also has this feature, every day you contribute to a repo, they mark that day in green.

Solicit feedback

If you already have some audience, try to get them to interact with you. If you start getting emails or tweets about your task, it becomes natural to put more effort into working on it. For example if you have a blog, at the end you could invite users to vote on new topics for you to write about. If you have a web app, you could add a live chat or feedback widget or prominently mention your email address to make it easy for people to reach out to you. If you receive a problem report this way, it feels wrong NOT to get to work immediately.

Install RescueTime

This is an app you can install on your computer that monitors which apps you are using. You can mark activities as productive or not productive. You can tell RescueTime that being in a text editor is productive, but being on Facebook is not. Based on this it knows how many productive hours you had and can send you a congratulation email when you reach your daily productivity goal and make you have an extra feel-good association with staying productive. To learn more, here's one in-depth review of RescueTime

Make a dollar

If you have a side project that you are currently doing for free, try asking for payment. Not because you are greedy, but because getting paid is a strong signal from others that they find value in what you are doing and want you to work on that thing. You might find that having even one person paying for your stuff will greatly increase how motivated you get in trying to improve it. If you feel like "I can't do that, I could let them down". Well, that's exactly the point, you'll get a boost of motivation from it. And if you really do feel that you let them down, there are always refunds.

Write a ridiculously detailed battle plan for tomorrow

Before going to bed, think about what the perfect day would look like. Maybe you would get up, get your inbox to zero, write some code, do some copywriting or have a nice session of exercise or study. If you can picture the perfect day, you could try writing it down in detail, down to the hour (remember to leave plenty of room for rest and breaks, too). Now tomorrow it will be clear what constitutes a success for that day.

Leave a small task undone

To jump start your productivity the next day, leave a task open from today. Before calling it a night, leave just one line of code unfinished so you can jump in and finish that as the first natural task for getting into a productive mood tomorrow.