How do you objectively ensure that you are following God’s plans rather than your own wishes?

My primary objective source is the Word of God. I've endeavored to study the scriptures over the years to discern what our Lord has given as his direction for our lives. This means the overall plans for all those who are committed to following our Lord. When it comes to our Lord's specific direction for my life I seek to test out what I discern to be his guidance with the scripture. I believe that his plans for my life will always be consistent with biblical truth.

A secondary source is the counsel of other people that know me and have demonstrated wisdom in life. These individuals have helped me check whether I am thinking clearly, and they help me clarify my own motivations. 

Here is my simple litmus test... it is found in 1 Cor. 10:31... Whatever you eat, drink, or whatever you do, you must do all for the Glory of God.  In this way you will be honoring Him and His plan for your life.

Too many times we become self-serving in what we do to ensure our wishes are met or granted. Even though our wishes may be God honoring...many times they are self-serving. Is it God serving or self-serving...that is my test usually...