Quote Originally Posted by Magnus Sporrano
I tend to like solid colored shirts with the kilt, as patterned shirts can be too busy when combined with the tartan. The exception to this is silk screened tee shirts which is fine for pubbing or bumming around. But at the office, I wear solid colors up top. I try to match the color of my shirt to one of the lesser used color in the tartan to help pull that color out. If I'm feeling particularly gawdy I've been known to wear a yellow fleece sweater with the Royal Stewart tartan but that's not recommended unless you are feeling like a complete outright attention whore.
Magnus has got it in one! Solid colours work best with tartan kilts every time. T-shirts and Polos are ideal for leisure wear.

I don't want (necessarily!) to keep promoting my 'other' Photo Album , but it contains somewhere around 90 images of my Kilt Kollection and shows just about every combination of shirt/kilt/footwear available to (this) man. The link is below.