I use this method and I know many others on other forums that do as well.
http://community.livejournal.com/feyeselftrimMy hair is tailbone length but I started using it when I was above waist and still use it.
Just be sure to use decent scissors. You can get a good pair at Sally for $10-25
But only use them on hair.
It is possible to use sewing scissors if you have them but make sure they are sharp. Cutting hair with dull scissors can do just as much or more damage as the splits you are trying to remove.
I don't know if you can afford $10-25 or not but if you can use that method and only pay that price once it's like buy one haircut get the rest free.
If you try that method don't cut too much the first time. And you might want to do a few practise runs with making the tail and sliding the bands down without actually cutting. Some bands might work better than others depending on how thick your hair is.
Good luck