Here's how you can cut your extensions at home, to produce layering and trim dry ends:
UPSIDE DOWN HAIRCUT
a) Wet hair
b) Bend over at your waist so that your head is upside down
c) Comb all hair forward
d) Point cut hair across in a straight, horizontal line
Note: Point cutting is when the scissors and hair are parallel, like this:
The deeper the point cutting, the more "thin-ness" you'll get at the ends for a more natural look.
NEVER CUT YOUR HAIR EXTENSIONS STRAIGHT (BLUNT) ACROSS, IT'LL LOOK FAKE.
ALWAYS USE A RAZOR TOOL, OR ELSE POINT CUT WITH SCISSORS.