The key to understanding people when they talked in Scotland was to decide that Scots is not English. Sure, they use a lot of the same words, and you can get by, but the differences are more than vocabulary. If you're on the bus before you're fully awake, and listen to the schoolkids in the seat in front of yours, it's a strong chance that you won't be able to understand them.

The vocabulary you can pick up pretty quick. (You only have to order a pay-stee once or twice before you learn that a pah-stee is a food item, and a pay-stee is way to increase your breast size.)

We became convinced that the ability to understand people was related not to their geography, but to their social/economic class. It was easier to understand shopkeepers than repairmen, for example.

The key, it seems, is to not get embarrassed, and to just learn as you go. (But be willing to learn, and adapt your vocabulary!) Kristin got the accent, I got a wee bit more vocabulary. Between the two of us we could make it work. (But, really, there's not that much language barrier.)