Scarborough is a very well established renaissance faire and the only one on its level in North Central Texas. Scarborough started in 1986 as just a few hobbit holes. Now it covers several acres (just guessing, I'd say around 30 acres?) filled with permanent buildings for the vendors and food sellers.
Parking is very good and very well run. If you get a "Friend of the Faire" pass, you get better (closer) parking. The parking is a system of gravel roads with the actual parking on grass. You can get stuck in mud but the one time it has happened to me, passerbys helped us out. There is enough grass that it will not be a mud pit. Remember the number of the road you park on.
Scarborough is open every year from the first weekend in April until Labor Day Weekend. Texas weather is completely unpredictable during this period. It can be 50 degrees one day and top 80 the next. It will take you the better part of the day to see all the vendors and, after catching a couple of shows, you should probably plan on getting in early and staying the whole day.
There are several ATMs throughout the park. Most of the vendors take credit cards but all of the food and drink vendors require cash. The alcohol is between $5 and $6 depending on what you get. They have domestic beers, some type of stout, a really good pear cider, margaritas and peach bellinis. There's more, but that is the most popular. The steak-on-a-stick is always good. Actually, I've never had anything I didn't like out there. The ice cream for the brownies and applie pie is a kind of soft serve that isn't great but I still love both dishes.
As for the shows, either print off the schedule from their site or spring for the program at the gate. I guarantee that you will need this program to get to all of the shows you want to see. If you don't know what you want to see, make sure to catch Don Juan and San Miguel, a hilarious Spanish sword fighting team. Zilch the story teller is also very good. There is also an excellent Birds of Prey exhibit.
The jousting arena is one of the only areas that has no shade. A hat would be a very good idea.
You can rent a range of outfits to wear for the day. Adults are $40 each and they have decent outfits but do not handle shoes. You can, however, get a good discount on the rope sandals if you have rented an outfit. The rope sandals are very comfortable and are machine washable. They run around $30 - $35 a pair. I think some are cheaper.
There is camping available but you are only a few minutes outside of Waxahachie. The closest hotel is the Texas Inn which looks like it is currently being completely redone and I'm not sure that it is open yet.