In this verse, King Solomon is saying that he is a black, beautiful man. In the ancient world, you had many nomadic groups of people. Saying
tents is a way to group those people, i.e.
tents of Kedar means the people of Kedar.
Kedar Dark-skinned Ishmaelites
Note There is a slight mistranslation on this verse: the word
but should really be 'and' as the Hebrew character in its place is a 'wa'