Hi laura i'ts great that you are interested in doing hair extensions ,
are you going on a training course with Balmain?
as there is loads of underpinning knowledge you will need to learn before you do hair extensions.
without training you are taking great risks of ruining someones hair
you will also need professional training for your insurance purposes too .
you could do a search on here for hair extension training good luck :hug: x
here is a link,