Simple.
1. First I figure out how I'm going to go about attaining the goal.
2. I then implement those measures and start moving towards the goal line.
3. When (and it will be "when" not "if") an obstacle presents itself, I either move it, jump over it or alter Plan A so the obstacle no longer stands in my way.
4. Make "Failure is the path of least persistence" your daily mantra.
Ergo, never give up. If you want something bad enough, you'll get it, regardless of the sacrifices you need to make. If you don't really want it, you'll never get it because that little voice in your head will convince you to give up because it's too much work, too difficult, too whatever. If you give in to that voice, you're doomed to fail every time.
Simple.