What are the different ways we sin

There are a great many kinds of sin. They can be distinguished according to their object all according to the virtues or Commandments that they violate. They can directly concern God, neighbour, or ourselves. They can also be divided into sin of thought, of word, of deed, or of omission.

• Sin of thought is when we use our minds or our thoughts to offend God.

• Sin of words is when we use our tongue to offend people and God.

• Sin of deeds is when we do things that go contrary to God's law.

• Sin of omission is when we failed to do that which God requires of us.

Even though they are different categories of sin, at the end of the day sin will always be sin. It is why Jesus Christ had to come and lay down his life for us. It is why he died. One of the mistakes we should avoid I think, is to think that one of sin is less serious than the other.

Ref. CCC 

Taken From The Compendium  - Catechism Of The Catholic Church