Let's say you are a fly on the wall. If you could listen to those around you, what would you want people to say about you? Of these things you would wish people to say, exclude everything said about you that pertains to your outward appearance and include only that which pertains to how you act and what you say to others; this is your character.
Building your character is like building a house. Some people are buidling their characters with faulty bricks, such as complaining, selfishness, laziness, and disobedience. At best, you will have a weak structure that, although it may look good on the outside, will fail to withstand the storms of life. Instead it will quickily crumble and decay.
Are you building a weak character? If so, you need to tear down this weak structure and start anew. They best way to do this is to repent of your sins and give your heart and life to Jesus. He can help us build good, strong characters with bricks like love, forgiveness, kindness, thankfulness, and obedience. These are sound bricks that, if built upon the foundation of Christ, will produce a good, solid structure that will last through every storm of life. In the end, it will enable you to attain heaven.
"Therefore, whosoever heareth these sayings of mine, and doeth them, I will liken him unto a wise man, which built his house upon a rock:" Matthew 7:24