I vote....don't saddle train!
At two years old, she's VERY much a baby. In my opinion, saddle breaking a two year old is like teaching a five year old algebra. Some will take to it like a duck to water, others could do with another five to eight years. I wouldn't even mention hard barrel work (consistently trotting, cantering, and galloping) until at least 3.5-4 years. Possibly even five years old.
I highly suggest working her on the ground, perhaps 10-30 minuets a day, until she is three or even four years old. Show her flags and tarps and bells and whistles, talk with her about it. Discuss this scary, spooky thing on the ground. Let her know that your completely okay with it, that your at ease and it's nothing to worry about.
I waited until my gelding was five before sending him to the trainer and I am very, very, pleased with how he has come along, compared to his temperament at two years old when I purchased him.
At two years old, he'd likely be cowering behind his hay bale in fear of the trainer taking him out to work, regardless how gentle my trainer is.
At five years old, he's matured enough to look at problem or a frightening object, such as a tarp or a horse trailer, and come at it in a thoughtful way.
At two years, the horse trailer was a pit of terror filled with snakes and things that go bump in the night.
At five years old, the horse trailer is an area that contains grain. Stretching for grain is uncomfortable, but stepping into the trailer equals more comfort. Standing with your legs stretched out is uncomfortable, putting hind legs into trailer equals comfort.
Henceforth, walking into the horse trailer equals comfort, grain, and cookies. If it moves, thumps, rattles and bangs, who cares? I have grain and cookies and this delicious pile of hay to strew about.
A lot of people who compete saddle train their horses at two years old because they want to get maximum show time out of them. They want to enter them in the younger classes which may or may not equal more ribbons.
This is really the incorrect way to do it. Just think about those young joints and muscles, think about the mind set of a two year old horse (grass, cookies, play time). They DO need time to develop mentally and physically as a horse, and not be put to work at the first possible moment.
Three is really the youngest age I would suggest beginning any real saddle work. At two years old, you can put the saddle on, cinch it, take it off, bit up, etc. etc. etc. IF they are MENTALLY ready for it. You wouldn't just throw a Wallstreet business man into the the jungle, you'd probably wait till he's mentally (and possibly physically) ready for it.
But hard work and actual riding should really not be attempted until they've mentally-and physically- reached that point ;D
I'm not bashing anyone who owns a horse trained at two, or who trains their horses at two. I just don't agree with it, and don't see the harm in waiting another one or two years before swinging up and asking them to do serious work.
Like I said, some take to it like a duck to water. Others, like my Red Man, need a little more time to stop seeing monsters in the shadows and start taking things more seriously.
Wait! I'll fix it....