Things I've learned, perhaps you may find useful

[Rob Janes]

There are a few common hurdles that I'm sure we've all faced at some time or another.  These are just some things that I have experienced and have learned from that will hopefully not fall on deaf ears and may be of use to some 'indies' out there looking to get a game going from start to 'close-enough-to-finish'

A)  Stay Focused!
    This is a HUGE hurdle that anyone who dabbles with 'indie' game development, and hobby coding has experienced.  It's easy to get side-tracked.  To work for weeks or months on a project, lay it down and never look at it again.
    We can attribute this lack of focus to many things; life, relationships, lack of creativity, lack of resources, overwhelming workload or a newer 'better' idea comes along.
    While I can't give advice on your personal life, when it comes to your project, my advice is to stay focused!
    Even if you have a better idea and you are SURE it will be even more popular than what you're already working on, stick with what you're doing.  Write your new idea down somewhere so you don't forget it and then keep plugging away at something you've already started.  Many projects get started but only few see it to completion.

B) Do it in moderation!
    Don't get burnt out by putting a careless number of hours into something and getting burnt out on the project.  Sure, you get a lot done quickly however you grow so tired of looking at the same project, that you end up laying it down for weeks on end until the passion to work on it stirs again. 
    Pace yourself, once you've got some major things done each day, (or even minor), call it quits and do something relaxing.

C) Don't nitpick
    This mostly applies to coders out there.  Once you've got a system or function complete, don't nit pick and try to make it perfect right off the hop.  Once it works and suits your needs, move onto another function.  Authors do not edit their work as they are writing it, and neither should programmers.  Once your work gets the job done, move onto something else…you can always come back and make it prettier later. (Sometimes this isn't the case, if it applies to key components of the game)

D)  Realistic Goals
    Let's face it.  The majoirty of population here are teenagers who are doing this as a hobby or to play around.  Don't aim to make a large successful game company overnight, or even within a year.  It takes time and patience, and usually for a business - an education.

E) Have fun!
Self Explained! Do what you enjoy!It'll make it that much more rewarding.

[VitinhooxD]

I like the D) part Sir.