Highland Day Wear or Evening Dress. Think of this as busines suit or Black Tie. The Kilt remains the same but all the other parts are different.
The Kilt is the beginning. Choose an 8-yard kilt of medium or heavy weight wool tartan. Light weight material does not drape or hold a crease well. Look at all the options for tartan in your clan as there are modern, ancient, muted, hunting, etc. There are tartans for different regions as well. The pleats on the back of the kilt are folded one of two ways: On the sett of the pattern or On the stripe of the pattern (military.) If you are not sure, do the sett as some paterns may not look great on the stripe. A kilt pin can be any design you like. It is pinned to the front apron on the right but only the outer layer.
For examples of pleating options see:
Belts with buckles are optional and often worn. For Day wear black or brown. I would not recommend wear with a waistcoat or vest.
The Sporran is your pocket. It is simple leather and can also be an animal head. This is worn with a sporran belt or chain. A band sporran (long horse hair) is only used by pipe bands and the military.
Pronounced "Skeen Du" (black dagger), it is worn in the right stocking. For day wear it is more casual as in a hunting knife. The more eleborate dress sgian dubh can also be worn for day.
For day wear, the wool stockings are of a muted solid color complimenting your kilt. The flashes or garter can be of tartan matching your kilt or a complimenting solid color.
Jackets are short cut for the kilt and can be in various colors and are often heavy tweed. There are different designs for the cuffs and most often have stag horn buttons. Frequently matching vest are an option. When wearing a tie, it should not be a tartan matching the kilt.
Ghillie Brogues in black or brown or any foot wear appropriate for the weather are used. Bonnets of the military style Glengary or the Balmoral are optional.
The Plaid is the long flowing tartan that originally was part of the kilt. This should be made of the same material as the kilt. It is worn over the left shoulder and attached with a broach. It is mostly worn with formal dress. This can be a Fly-Plaid (as shown in the photo) attached only at the shoulder or the more formal Belted-Plaid attached at the waist as well as shoulder.
Dress sporrans are more fancy and usually fur with various embellishments. An animal head may also be worn.
The dress sgian dubh is black handled decorated with studs and often a jewel.
For evening wear, a custom tartan hose matching your kilt is the most elegant but also expensive. Sometimes ready-made tartan hose may be close to matching your kilt. In the past white hose were in fashion (only for evening), but now the fashion is for black, navy or charcoal. Military diced hose can also be worn. They are in black and red or white and red.
The most popular jacket is the Prince Charlie most often with a waistcoat or vest. It is a tail coat with the tails shortened. There are other doublets in different styles.
Black Ghillie Brogues are appropriate.