Since this will be your first kilt, and since you've stated you want to wear it to represent your clan, then your best choice would be a traditional 13 ounce wool kilt. Either a box pleat or knife pleat kilt is acceptable. If you opt for a knife pleat kilt, then you have the double option of having it pleated to the sett, or to the red stripe. The choice is yours.

You are also going to need hose to go with your kilt-- Colquhoun is a great tartan, and would look good with either dark green or Lovet green hose. Red flashes will look fine, and won't cost as much as tartan flashes, which many (myself included) consider "tartan over-kill". I would strongly suggest that you buy two pair of hose-- one in a lighter shade and one darker. Avoid white, creme, or ivory hose. White is the colour of pipe band hose and the hose supplied with rented kilt outfits. Creme and ivory always have the look of white hose that has "yellowed" due to improper laundering. White hose also soil quickly-- a half a day on the field at a Highland games and white socks look dingy.

You will also need a sporran. Since you are starting out, a plain black or brown leather sporran will do nicely. You do not need to splash out on anything fancy. In all probability 99% of your kilt wearing will take place during the day, or in the evening in casual surroundings.

You will probably want a kilt belt (properly called a dirk belt), although it really isn't required (unless you are sporting a dirk, but the less said about that the better!). If so, I'd suggest plain black--

For someone just starting out, plain black shoes-- highly polished-- are perfectly acceptable. They can be wing tips, ordinary lace ups, or loafers. There is no need to spend the money on "ghillie brogues". The advantage of "go any where" black shoes is that as long as they are polished, they look good at any time of day, or night. The same can't really be said of brown shoes.

I'd suggest, at least in the beginning, that you stick with a white shirt-- long or short sleeves is a matter of personal choice. It presents a smart appearance if you are representing the Clan Colquhoun in their tent at a local Highland games, and with sleeves rolled up it is perfectly casual. White looks good worn with a sweater, or a dark wind breaker on a chilly day.

Good luck!