Two moves grow sales in the fitting room: get every shopper to try it on, and keep handing them options while they're in there. The room is where one item turns into an outfit, and most stores waste it by pointing shoppers at it and walking away.
Start with this: the sale isn't final until somebody tries it on.
Apparel bought without trying comes back, and apparel never tried never gets bought.
Everything about your fitting room process should push toward getting the customer in the room.
Then comes the part that grows the ticket: stay there. Don't just turn and go back to the register...waiting.
While they're trying on, you bring options. A different size before they have to ask. Another color. The jacket that goes over it, the shirt that goes under it. A person in a fitting room is, put plainly, half-naked and open to suggestions. They can't leave, they're already imagining a different version of themselves, and every option you hand over the door is a possible second unit. This is where one item becomes an outfit.
It is how I built an apparel retailer to win the highest increase in sales at South Coast Plaza, the number one mall in the world.
Guys were notorious to say, "I know what size I need," and I'd say, "Well, if you want to look the same, yes but if you want to look better, I can do that...if you try it on."
For the shopper who says "I don't want to try it on," find the reason it's worth their time: "When you try it on, we can custom fit it." Whatever is true for your store - hem, tailoring, checking the shoulders- give them a benefit for walking those ten steps, because ten steps is the distance between a maybe and "I'll take it"
The associate who parks near the fitting rooms with an armful of options will outsell the one straightening racks every single week. Your rooms are already built. The mirrors are already paid for. Develop a system to use them.