There are many ways to give alms during Lent. The key is to find a cause that helps your neighbor in need through the corporal works of mercy (feeding the hungry, clothing the naked, visiting the sick and imprisoned, burying the dead).
Here are just three simple ideas to get you started on your Lenten almsgiving mission. 
Service: Seek out a service project with a local charity. Give time. Example: Volunteer to pound some nails with Habitat for Humanity,
find your local food bank and offer to organize the donations that come in, or help at your local soup kitchen.
The piggy bank: Set up a Lenten almsgiving “piggy bank” in your home.
This is especially instructive and fun for children. It will help to teach them that Lent is a season grounded in sacrifice and service.
Think like a Medici: Each one of us has the ability to be like a small-scale House of Medici, the family of influential patrons of 14th-century Italian art. Find a charity that your family wants to support and be its patron.
Almsgiving is just one of the three pillars of Lenten service; the others are prayer and fasting. These three pillars go hand-in-hand and should be a regular part of your Catholic life, not just a seasonal Lenten practice.
There are 960 hours in Lent. How are you spending them?