The first thing is to wash your hair to remove dead skin from the scalp. Before you cut your hair, take a shower and massage your head properly while shampooing. You need to use a conditioner as well after washing.
In the next step, you are to wrap a towel around the head in order to remove excess water. However, do not dry completely, as the hair need to be wet when you cut them.
Grab a fine-tooth comb and part your hair while removing all the tangles, as styling tangled hair is not only difficult but also causes breakage.
Now you need to decide the length of the longest layer that you want as this will be the exact length of the hair once you are done cutting.
Take a sharp layering scissor and begin by cutting the hair from the back. You need to cut them straight, so it is advised you comb them first.
Now you need to work your way up to the shortest layer. Grab a section of hair in your hand and hold it at a 95 degrees angle to get an idea of the sections which require trimming. Just repeat the process for every layer.
No matter how precise you are while cutting, you will probably miss a few portions which you will notice later, so instead of waiting for that to happen, just brush or comb the hair down and look for any layers which might seem uneven to you. After locating the stray layer just cut that portion and comb the hair again, you need to continue doing this until the layers are even.
After finishing, just style your hair the way you want them and have fun.