Although there isn't a sales section for UNIQLO, there are certain times in the year where they offer different promotions.

Along with promotions, UNIQLO teams up with different companies or organizations to offer collaborated apparel. For example, there was a time when they were selling limited edition Hello Kitty clothing. Also, when Japan was hit with a massive Earthquake that killed thousands, they sold T-shirts to help the relief. I walked into the store during that time and there were many t-shirts saying "Save Japan." I specifically remember one of the T-shirts saying, "with all my heart, to Japan."
UNIQLO doesn't have many promotions throughout the year, such as not offering lower prices during Black Friday, but they are very big on their advertising. Just like I said in my post prior to this one, UNIQLO advertises on trains, buses, cabs, and billboards. Advertising is an important part of how they get the attention of their customers.