Just a couple of tips. My dd has the unruliest of hair. She actually decided this year to cut it would be short enough to do a curly pony but she has tons of flyaways around her face and an uneven hairline. Really, a nightmare for smooth finishes.
Clean hair is super slippery. I find everything stays in place better with dirty hair. So, I have her not wash it with shampoo the few days before the meet and then I just have her wet it in the shower or spray it down with a spray bottle right before I start. I like to let it dry just a touch before starting, I find it hard to get out the lines from the comb/brush if the hair is too wet.
I have this very fine tooth comb with a pick on the other end that works awesome for dividing hair and smoothing. Two tools in one.
Two hairties are better than one!
Gel, Gel and more Gel! Any store brand that says stiff or super strong will work fine. I do find that if I put it in her hair and then immediately try to do her hair while it is still all over my hands it gets sticky and is harder to control. So I put it in and then wash my hands before starting.
I totally agree about practicing and putting them in front of the TV. Keep them still and occupied and it will go a lot quicker.
It doesn't seem to matter which style I do it still takes way longer than I think it will so I always leave at least 45 minutes. Maybe longer for you as her hair is so long. It should take less time as you get better at it, but any way about it it is an undertaking.
If she has an early morning session and I use lots of gel I can usually get the front part of her hair braided the night before and a little extra gel and hairspray will fix up any flyaways in the morning.
Good luck and make sure to post a pic so we can celebrate your meet hair victory with you