Why do Catholic Cross Themselves

They need to use the bathroom.

No,  "[I]t is not instructed by the Word of God..." full text: Sign of the cross - what is the meaning? http://www.gotquestions.org/sign-of-the-cross.html

You'll also see people kissing a crucifix. This is an act of indulgence (one of many false teachings of the Roman Catholic Church).

[Proclaiming The Gospel Ministries by Mike Gendron] "As a Roman Catholic for over 30 years, I was taught from the Catechism that salvation was by faith plus baptism, the sacraments, good works, law keeping, the sacrifice of the Mass, indulgences, purgatory and penance. According to God's infallible word, this is another gospel that deceives Catholics with a false hope. Only when Catholics trust the Lord Jesus Christ as their all-sufficient savior will they know they are saved completely and forever!" Full text:  Proclaiming The Gospel Ministries 

Why do Catholic Cross Themselves