1. Get to know them as well as you know your best friend (caution, takes time)
2. Get to know their work and find out what they are actually doing. (Friendly)
3. Get to know what they like (bagles, pens, notebooks) and send them one once in a while.
4. Become a part of their lives and tell others.
The way it works is, what would you want others to do if you were in ministry, normally in a foreign country and speaking a different language.