Thinning scissors with rounded tips (can be found in tack shops,  pharmacies, hair salons, etc.)
Horse shampoo and conditioner
Mane detangling product
Brush and/or comb

Step 1:
For best results, wash the mane with horse shampoo and conditioner. Make sure to follow the instructions on the bottles carefully and rinse out all products (unless otherwise stated in instructions). Brush the mane thoroughly; if necessary, you may use a mane detangling product at this stage.

Step 2:
Using thinning scissors (which will create a more natural look because not every hair is snipped with each cut) start cutting from the base of the mane. Cut on an upward angle, with the middle of the scissor blades at the desired length you want the mane to be. Make your way all along the mane without cutting the same area twice. Brush out all the loose hairs that have been cut.

Step 3:
Do the same thing in the other direction, starting at the top of the mane and working your way down. The scissors should now be pointing in the opposite direction and still be on an angle. Brush out all the loose hairs.

Step 4:
Keep repeating steps 2 and 3. You should notice the bottom of the mane getting progressively thinner without leaving a perfectly straight edge.

Step 5:
Once the mane has been completely cut through and you have brushed out any loose hairs, do any touch-ups by cutting straight along the edge. To create an even softer and more natural look, hold the base of the scissors close to the horse’s neck and point the blades of the scissors out away from the horse. Fluff up the mane and only trim the tips of the top layer. Now all that’s left to do is brush one last time and admire your horse’s brand new look!