Tomorrow will be my first day of Fasting and I've been reading about it.
I found this article with some helpfull teaching about fasting...
The enemy makes you a target because he knows that fasting is the most powerful of all Christian disciplines and that God may have something very special to show you as you wait upon Him and seek His face. Satan does not want you to grow in your faith, and will do anything from making you hungry and grumpy to bringing up trouble in your family or at work to stop you. Make prayer your shield against such attacks.
Do not become so caught up in praying for yourself and others that you forget about simply reverencing and praising God. True spiritual fasting focuses on God. Center your total being on Him, your attitudes, your actions, your motives, desires, and words. This can only take place if God and His Holy Spirit are at the center of our attention. Confess your sins as the Holy Spirit brings them to your attention and continue to focus on God and God alone so that your prayers may be powerful and effective.
From the Campus Crusade for Christ.
"so that you do not appear to men to be fasting, but to your Father who is in the secret place; and your Father who sees in secret will reward you openly.
"Now, therefore," says the LORD, "Turn to Me with all your heart, With fasting, with weeping, and with mourning."
Do not deprive one another except with consent for a time, that you may give yourselves to fasting and prayer; and come together again so that Satan does not tempt you because of your lack of self-control.