I found this tip from this website http://www.superherodesigns.com/journal/archives/2011/02/06-week/
and I liked it so much that I'm passing it on.
I've read that keeping a gratitude journal helps contribute to overall positivity and happiness and while I agree, it's been hard for me to keep one. Because really, at the end of a crappy day, who wants to feel grateful? The lady at the blog basically said the same thing and mentioned that she and her family discuss their favorite part of the day. So I'm doing the same thing and it's much easier to focus on your day b/c there is always something, even if your day is horrible. Example, yesterday wasn't a great day for me, so my favorite part of the day was going to sleep.
Anyway, just thought I'd share what is working for me.