I was told it goes on the right, so that with your targe on your left arm, you can draw it easily with your left hand; your broadsword being in your right hand, of course. The broadsword scabbard is hanging from a baldric on the left side.

No broadsword? Oh, dear. According to the "traditional" rules, which are usually taken to be what the Victorians favored, the style was to clap on as many weapons as possible, including all the edged weapons cited above, plus the sgian dubh, a couple of Highland pistols stuck in the belt, and a powderhorn. The claymore was optional.

Nowadays the sgian dubh is the only one still common, but losing ground in the face of security concerns and weapons restrictions; the dirk is almost gone, and the others have disappeared in polite society. Pity. What a spectacle was such garb--plaids with jeweled brooches, enormous goathair sporrans, displays of polished leather and gleaming silver--but I digress.

Congratulations! Wear that dirk wherever you feel comfortable and you'll make a fine show, I'm sure.