A fashion agent holds the designer's collection in their showroom so that store buyers can make appointments during fashion week to view it and place an order.
Depending on what the contract is between the agent and the designer, a typical day would include liaising with the designer to find out how the new collection is taking shape, or how manufacturing is going (will the stores receive their orders on time?), chasing payments from stores, calling buyers in to see a new collection etc. They work on a commission basis, usually taking 15% of each completed sale.
They would hold several collections every season in their showroom to ensure they make enough commission to make it worthwhile - but it's also better for the buyer if they can see many suitable collections at one time. Agents try to have complimentary collections...nothing too similar that they conflict yet not too different that they will appeal to different buyers.
They may also show on the designers behalf at trade fairs in other countries/cities in order to bring in more business.
Some also act as press agents, but usually pr and sales agents are separate.
Finding a good one isn't easy and you need to find an agent who will work with you and respect your collection and believe in what you do. It depends on what you design and who you want to sell it to, but some agents are only after the money and will sell to anyone who asks. Others will hold out to sell only to the best stores as this obviously has greater longevity.
http://www.rainbowwave.com/ is a sales agent for designers such as Cacharel, Tomas Maier and Rafael Lopez.
Sorry if this doesn't make complete sense, it's late and I'm really tired!
