I second what a few people have said here...
Being British, I don't watch an episode when it is initially aired... granted I get to watch it usually the next day, but not always. The difficulty is, that before the episode is aired, usually the spoilers are not that dangerous, unless it is a big episode then there is a risk of learning too much, or more than you maybe wanted to know.
It's dodging the temptation, after the episode has aired, and before you get to watch it... to read what other people are saying about an episode. Especially in recent years, I have not really cared about the episodes all that much, so I have been frequently tempted to read feedback after an episode to determine if it's worth me bothering to watch it... sadly, this often means I learn who the killer is, or what the motive was, which can spoil the episode entirely for you!