Don't go into a cafe and order a 'half latte'. chances are they won't understand what you* mean and will end up making you* something that has too much milk, and you* will be complaining about it every time you order a coffee.
Order a PICCOLO. It is Italian for small. And will generally be a latte made of milk to coffee ratio of about 2-1.
If the cafe doesn't know what a piccolo is, refer to TIP 3.
*you = my dad