Giving can be more than monetary. It might be taking someone to the park or to visit a friend. You might find a way to make the life of someone else easier. We can pray. Prayer can make a difference in someone's life including your own.
Prayer is an act of righteousness.
We can fast. This may not appeal to you. We can focus totally on God seeking his guidance and help. It can show our sorrow and deep repentance. None of our acts should be done for show or frivolously.