A simple white t-shirt is the perfect thing to wear with a block of big, bold and bright colour.
Jil Sander used this technique in her Spring 2011 collection
Some ideas from items on the high street. A white t-shirt will look good with these pieces because they won't detract from the great colours of the pieces and will keep the look clean and simple.
PLEATED SKIRT BY RARE** - topshop
Unisex Stretch Twill Slim Slack Lite - American Apparel
A white t-shirt will look great with complicated prints, especially small detailed ones. It breaks up the look and stops it from being too fussy
YELLOW SUNSPOT PRINT SHORTS - Topshop
A really cool evening look is to wear a simple white t-shirt and then pile loads of necklaces on it to make it more eveningish. To accomplish the look you should wear necklaces that are a range of lengths, but to keep the look from being too random wear either just gold/bronze necklaces or just silver necklaces. A variety of different types of chains makes the look more interesting. The necklaces also shouldn't have too many brightly coloured charms or it makes the look messy.
BEATEN RINGS DITSY NECKLACE - TOPSHOP
The last way I'm going to mention is wearing a white t-shirt underneath items, such as layering them under other t-shirts, wearing it with an open shirt over it and wearing it under a dress to make it more casual.
Here are some examples of items that would look great with a white t-shirt underneath
Sleeveless Lace Chiffon Dress - AMERICAN APPAREL
Thick-Knit Jersey Cross-Back Short-All - AMERICAN APPAREL
Hope you now all understand the amazingness of a PLAIN WHITE T-SHIRT