The most common challenge new users of treeless saddles experience is mounting.
Treeless GHOST saddles should be mounted using the same technique as English saddles.
Stand close to the horse
Grab reins and mane with the left hand
Place the right hand over the saddle, so it lays near the offside thigh block.
Mount quickly and cleanly.
DO NOT mount by grabbing the pommel and cantle. This will damage the saddle, possibly injure your horse's back over time, and will cause the saddle to slip.
Here is a helpful video demonstrating correct mounting technique.