Multiple MarketPress Stores In Multisite

I was able to follow directions for activating my WordPress for multisite, but once I was in it, I didn't know how to accomplish the following:
I have an online store for one of my customers already on my website. I made the store with the MarketPress plug in. What I want to do is create the following stores as well, all contained under the Blue Dog umbrella.

Holiday Cards (would be http://www.getbluedog.com/holiday-cards)

Tshirts (would be http://www.getbluedog.com/tshirts)

Mary C Howse Spiritwear (would be http://www.getbluedog.com/mchspirit)

East Bradford Elementary Spiritwear (would be http://www.getbluedog.com/ebspirit)

I would want all of the "substores" to keep the same Tempera theme and keep the same look that I currently have for the Balfour Beatty store.