Generally speaking, there is no rule about where portraits are painted. After all, the portrait looks at whether it is similar to your model after painting, not as a painting process.

But in a strict sense, when learning to sketch an avatar, especially in the primary stage, we must first find the big outline of the head, because only when the frame is done can the contents be comfortable. After the big outline is drawn, the shape of the five senses should also be shown accordingly, and then the facial outline should be adjusted according to the ratio between the five senses and the facial outline.

In the process of sketch learning, it is advisable to draw the facial features first, but it should be noted that when you choose to draw the facial features first, it is the performance of your partial painting, and it is easy to ignore the overall feeling.