The hairs of long-haired dogs will grow very long and thick. Don’t cut them first. Clip them on the top of their heads with a clip. First trim the hairs under the ears, then put the ears down and trim them. This way the shape of the ears can match the shape of the entire face.
After clamping the ears on the top of the head, it will be much easier to cut the long hair on the face. Trim the hair on both sides of the mouth to the look you like. I usually don’t cut the dog’s face very hard, so that the sides of its mouth should be kept oblong as much as possible, so that I think it is more cute. As for how to cut your dog, it's up to you.
This is the little face on one side of the dog. You can see that the fur on the left is 5-6 cm shorter than the right side, and then trim the right side with the left as the standard.
When trimming the other side of the face, the standard is based on the trimmed side. Both sides should be symmetrical to look good. In addition, you can cut off the hair dyed yellowed by saliva on your mouth with your hands, so that your dog's small face will look particularly clean and neat.
When trimming under the neck, under the belly, and around the eyes, it is safer to have someone help to fix the dog, because if the dog moves around these places, it may endanger its life. Of course, this is not absolute. My dog is super well-behaved, and I can handle it alone. I just need to introduce the safest way to you, so I suggest you take action when someone helps.