The third traditional expression of penance or conversion is called "almsgiving". This is not simply making sure we put a coin in a charity tin (although there is nothing wrong in doing this of course). It is important that we use our financial resources to the glory of God. Lent can be a time for us to assess how we use those resources. The reason for this is that the way we spend our money can reveal something about our priorities in life. One very good exercise is to look at a bank statement or two and go through the items reflecting on how it might say something about our priorities. As all our wealth is ultimately God's, and we have it as custodians, we need to remind ourselves that we need to justify our use of His resources and say sorry when we misuse them. We also need to ask ourselves on a regular basis, "what does my Lord want me to do with His resources that I have?" Of course He wants us to have a good and healthy life, and He is not against us enjoying ourselves. But have we been too lavish in spending on selfish things? And too frugal in spending on others? We also need to remember we need to give realistically to the Church so that its mission and purpose can be fulfilled in the world.
More generally we can also usefully reflect on our lives by how we spend the time we have been given. And I think there is nothing better than the Corporal and Spiritual works of mercy (above) if we are ever at a loss as to what to do for the Lord.
Lenten counsel no 5 - have a little spiritual audit of how you are spending your money, asking how much is selfish and how much benefits others. Remember it is not actually your bank account but the Lord's! He will ask you one day to give an account! Also think about your use of time - and perhaps think of a Work of Mercy to do each day.