Every once in a while write down what it is you are doing to achieve that long term goal your striving to achieve. If you find that you are way off course - don't worry; just re-map a new route to that goal but never give up: persistence and perseverance should, if they aren't already, be your metaphorical best friends.
Life is short but the only way to manoeuvre around it without wasting what little time we have, is to always set challenging long term goals. That way you don't find yourself, years later, looking back at it all thinking how aimless it was or regretting how long you spent bumbling at the bottom.
Interesting blog post on the topic: Why not...Invest in your dreams?