Getting Baytril injection to fight R.I

I have a 2 yr old b.p fighting a R.I. Just took her to the vet a few days ago and she was prescribed a antibiotic injection (baytril) she has received two injections now. The first one done at the vet and I was shown how to give her the injection. Naturally though she hates it and even with two people holding her down we have a tough time getting the needle into her cause she flails around so much. She's only about 2 foot long and weighs 180g so she's not very big. Anyone have any good methods off keeping them still enough just for me to get the needle up under a scale and injecting the medication?

Main method I've seen is tubing, which means getting a capped tube just larger than the snake and letting it crawl/guiding its head and upper section into it. Makes it easier to restrain them for shots since the tube keeps them from flailing too much.