Today, Ash Wednesday, is the first day of Lent.
For many Christians, now is the time of fasting and repentance. The time to let go of bad actions and concentrate on becoming better. The time to 'give up' something that is difficult to go without (think chocolate, coffee, internet...). During times of cravings of the given up something, remember the sacrifices Jesus made for us. In comparison to that, [insert your given up something] doesn't seem like such a difficult thing to go without for 40 days (plus Sundays).
Lent is also a great opportunity to spend more time in God's Word. Spend time in the Gospels (Matthew, Mark, Luke and John...first four books of the New Testament) and learn how Jesus lived His life. How did he deal with conflict, with demands on his time, with haters? Is it possible to learn to live a better life by reading about His? I do believe so.
You don't need to be affiliated with a church/denomination to practice Lent. It's a personal journey.