The multi-layer covering method is defined relative to the one-time drawing method. In one-time painting, the shape and color of the object must be balanced, while multi-layer oil painting is carried out step by step. Firstly, accurately or roughly outline the sketch relationship on the base color layer, apply a thin layer of color without considering too much detail, and then lay a covering layer. Ancient European masters usually used a one-time painting method when laying the covering layer, which can maintain the liveliness of the picture. Tanpeira pigments are also commonly used as the base color layer. Tanpeira pigments have low oil content, dry quickly, and can improve the brightness of various colors in the covering layer.

The current multi-layer covering coloring method is different from ancient times. Mr. Quanshan Shi's "freehand style" portrait painting also adopts a multi-layer covering method. After the monochrome drafting, the broad No. 12 oil painting brush dipped in the diluted color of Turpentine was used to spread the body color, and the picture presented a fresh and elegant watercolor effect. Then the elastic large bristle brush was still used, and the "three in one" color mixing oil (one for color mixing oil, one for gloss oil, and one for Turpentine) was used to shape the body with strong strokes, and the cold and warm contrast of the picture was enhanced with bright colors. Before the third layer of color coverage, spray a layer of connecting oil to facilitate the connection of the paint layer, and then use a combination of a scraper and a paintbrush to deeply shape it. After accurately and meticulously sketching the sketch, painter Yang Feiyun tried to use large and medium-sized brushes to spread the picture directly. Next, he used small brushes to further shape the head of the figure. Finally, he used a paste medium (mixed with mature oil, which can be diluted with Turpentine) to dilute the color, and still covered the head until the final adjustment was completed.

The coloring of the covering layer should be completed as much as possible once or in part at a time, and the base layer must be dry to prevent oil absorption. According to the ancient European masters' principle of 'fat covers thin', the pigment used for the covering layer must have a little more oil than the base layer. The bottom color should be thinly applied after being diluted with Turpentine, and the toner should be used for the covering layer. Adding a little white pigment to the colors used in the covering layer, whether necessary or not, can prevent the color layer from turning black and cracking afterwards.

Using a unified color for the base layer is easier to achieve a harmonious visual effect than using solid or contrasting colors. So try to avoid too strong colors in the base layer and focus on improving the sketch and styling.