bohyme french wave for micros

 I want to get micros and i like the bohyme french wave, i love big hair..would i be able to use it for micros and i dont know how to figure out how much of hair i need, i usually just guess and end up buying too much but that hair is too expensive for me to do that..Please help me and where is the best place to buy it and what length..i need it to match my hair which is 27/30 mix