职业插画师必备的素质及技能如下：

绘画技能：掌握基础的绘画技巧和理论，如色彩理论、透视、光影等。熟练使用不同的绘画工具和媒介，如铅笔、水彩、油画、数字绘画工具等。

创意思维：具备创意思维和想象力，能创作出独特和吸引人的作品。

视觉表达能力：能通过视觉元素有效地表达想法和情感。

数字技能：熟练使用数字绘画和设计软件，如Adobe Photoshop、Illustrator、Procreate等。

观察力：具备敏锐的观察力，能捕捉和描绘生活中的细节。

品质：持续学习、耐心和毅力、时间管理、开放性、良好的沟通能力、商业意识等。

The essential qualities and skills for a professional illustrator are as follows:

Drawing skills：Master basic drawing techniques and theories such as color theory, perspective, and lighting. Proficient in using different drawing tools and mediums such as pencil, watercolor, oil painting, digital painting tools, etc.

Creative thinking：Have creative thinking and imagination to create unique and attractive works.

Visual communication skills：Able to effectively express ideas and emotions through visual elements.

Digital skills：Proficient in using digital painting and design software such as Adobe Photoshop, Illustrator, Procreate, etc.

Observation skills：Have keen observation skills to capture and depict details in life.

Quality：Continuous learning, patience and perseverance, time management, openness, good communication skills, business awareness, etc.