There are different ways to fear God, just like children fear their parents. Some children fear the wrath a parent may impose upon them so they avoid certain things. Others avoid things because they don’t want to hurt their parents. They love them and respect them, and it is out of this love that they fear offending.
This is as simple as it gets. It’s ok to fear the wrath, but even better to be fearful of offending.
I have found that certain books are helpful in developing conscience. Try something like, “My Daily Bread”.
Frequent confession is also important - at least monthly. If you have no serious sin (mortal), then discuss the less serious sin (venial). This is where you develop a sense of virtue. Explain to the confessor that you desire to grow in holiness. He will give you advice.
Make sure you understand each of the mortal and venial types of sins.
More than anything, pray that the Lord reveals to you in your heart those things that are displeasing to him. If you should be troubled with a pattern of repeated offenses, or a habit, you must dig deeper to make some kind of structural change to remove it. Remember the saying that if your right arm makes you sin, cut it off. I am surprised after some really deep soul searching just how too much TV led to not only a less virtuous self, but even led to mortal sin. There are programs I no longer watch and I have found comfort in using those times to read spirtual books or watch EWTN.
Peace!
Diane