The job of the costume department is to bring the Designer's vision to the camera. The job of the Supervisor is to put the department together and run it. In reality all the Designer has to do is choose the clothes for the changes. Sometimes the Designer wants to manage every facet of the department. It is the Designer's department and a Supervisor has to be able to manage according to the desires of the Designer.
The approach to supervising is like constructing a building. Make sure all the parts are in place, hire the best people you can afford, track the budget and schedule. Make sure everybody does is doing their job. Every show has different demands and specialty work comes up all the time. Sources and vendors have to be lined up. The crew has to be people that can be depended upon and get along together. If you track the money daily you might be able to stay ahead of accounting. Everyone should try to accomplish duties with the thought of what would happen with a car wreck in the morning. Any Costumer should be able to walk in and pick up where someone left off.
The first step after getting a job is to break down the script. It is done by reading it once, then reading it again making notes as you go. It is not always clear how often characters change clothes or when script days change. Background count and type is guessed at based on the budget of the show. Research begins based on the level of detail in the production value. Are uniforms specific to locations or non-descript?
Next is to come up with a budget that includes man-days. Usually the Designer will tell you about what is going to be spent for each character based on what stores are going to be shopped. Sometimes adjustments can be made for certain changes, like pjs are going to cost less than a suit. Those are usually the kinds of adjustments you make after the first budget has been rejected. Man-days are a function of how many actors are in the day's work. For contemporary BG a Costumer could handle as many as 50 if BG are bringing changes. With prefit period shows the number is more like one Costumer to 20 BG. A Costumer should be able to handle about six principle actors. Those numbers depend on the costumes and the budget.
Make sure accounts are open and expense accounts are running. Accounts should be local when possible. Infrastructure has grown and is still exploding so a list would be out of date soon after making it. Not everything is in Atlanta and not everyone understands movie scheduling. Most movies want to pay with a Payment card, check or cash. Return policy needs to be known before purchase.
Is the film big enough job to bring on someone to track the books? A process of tracking expenses has to be set up so that filling out reports is easy. A scanning system is preferred that allows the data to be searched. Always try to return items as soon as it is known that they are not going to work. Returns that pile up tend not to be made.
Wrap begins with the first several days of prep because good organization is key to wrap. The space has to be set up for work, including fitting rooms. How much sewing does the script demand? How much aging and dyeing? How much clothing stock and where is it coming from? If rented, it must be checked against the packing list provided from the house. Any multiples? How is it going to be organized in the warehouse? Character stock has to be organized by character with easy reference to return dates, costume house, assets or whatever other data the show requires. Supplies need to be ordered. Every show is going to have different needs. Is it bloody with stunts? Uniforms?
Time to bring on the crew. Is there going to be an Assistant Designer? How many Key Costumers handling what responsibilities? How is the truck organized and how will the set be handled? What is the plan for off set costumes? The main ingredient is for the lines of communication to be reliable. A Supervisor should hear of a costume problem from a Costumer first.
The general rule for Production Assistants is they can't touch cloth. They can take food and coffee orders. They can procure supplies and expendables. They can do paperwork, from accounting to signing in BG. They can do returns as long as a costumer has bagged them with the receipt. They cannot shop. They cannot unload costume rentals. They cannot sort costumes. They cannot fit BG. Costumers need to be doing costuming.
The logistics must also be planned out. Where are the fittings going to take place and how are fitted costumes getting to set? It is always best to avoid transporting costumes in personal vehicles. What is the plan for cleaning?
A Supervisor must track work. How is the flow through the sewing shop? How is the documentation in the continuity book, up to date? What does the prelim and call sheet demand from costumes? All script and schedule changes need to be noted and kept up to date. Look for bottlenecks in the workflow. It is easy for alterations to pile up the days before filming starts or dirty BG stock to pile up.
Whenever possible, wrapping as filming proceeds is the best approach. Wrapped day players costumes can be cleaned, tagged and bagged and put on a wrap rack in the warehouse. Costumes that are rented can usually be returned after the needed scenes are shot out. If they are rented for run of production they can still be wrapped to ship.
The Unit Production Manager will tell you what characters are going to be kept. If there are any rentals, they need to be noted and returned to the rental house. Go the extra step in packing rentals. Work to make sure the rental house gets the costume(s) back better than it was packed for shipping. That's not usually a high bar to clear. Everything not kept has to be disposed of through sales, donations or liquidating contractor.