What is considered chaste behaviour from a Catholic perspective? The Catholic church teaches that sexual love between a man and a woman is to be reserved to within marriage.

My question is in the opinion of the Catholic church what is defined as pre-marital1 sexual activity and what is considered chaste behaviour? It seems from the little information I have found on it that intention, action and result are all to be considered. However, what is considered unchaste, for instance would any activity that can lead to orgasm be considered unchaste? Would tender kissing to show affection be unchaste? Would the same action be unchaste if it were for sheer enjoyment? 

Or perhaps is there some other definition or key idea that I am missing? 

1. i.e. For the unmarried
I kind of think the answer to this question is purely pastoral.  It's not in any Encyclical or the Catechism, but the answer comes to a person who forms their conscience well and the Church has a lot of guidance on how to form your conscience. 


Seek first the Kingdom and the Will of God. 

Marriage (and the acts that follow) is what God calls man to most of the time,  we can tell it's His will through the natural law (it's the only way we're going to get anything accomplished) and because He said so "Go forth and multiply" in Genesis a few times. But, even though it seems obvious that you should just have sex right away. It may not actually be the right person you're having sex with therefore:
Pray with (and for) your future spouse 

In one very Jewish story that only Catholics and Orthodox seem to remember is the story of Tobias who, not wanting to be killed on his wedding night by the demon in his wife, prayed with her before the consummated their marriage. And
Pray for purity every day

This is a pretty concrete and well known practice of praying three hail mary's before bed for purity of heart.  Purity is something you pretty much always get when you ask for. 


So, I know that you probably think that didn't answer your question in the least, but that's the approach a Catholic might take in forming their conscience towards the questions that you raised.  

What I, as a Catechist, would tell my students if they asked how far they could go with their boyfriends or girlfriends.  Is that the purpose of dating in null, what they need to do is court.  That involves knowing the entire family of ones future spouse and getting to know them intimately so that you know if your heart is in the right place.  Kissing, other than customary kissing, shouldn't be a part of that pre-marital relationship.  You shouldn't have any sexual intimacy that would be reserved for marriage before marriage.  That would be unchaste.  

Chastity is a virtue, not a verb, like all virtues, it's really a spiritual muscle that can be worked up over time to just react rightly in all situations.