Creativity might just be the most important skill for a visual effects technician. Unless an effect exactly replicates one that the technician has done before, the technician has to come up with a unique and creative way to meet the director's vision on every project. This requires combining basic techniques with the visual style of a film, all while staying within budget to create the effect that the director wants. The more creative someone is, the better the person becomes at finding solutions to effects problems.
The ability to learn very quickly is essential in the special effects world, especially because of the compressed time schedules films are often shot on. A special effects worker might need to learn pyrotechnics and mechanical or model-making techniques in a very short time frame. Some crews learn from each other when each member has different experience in the industry, while others need to do research or bring in consultants to quickly get up to speed on a new way of creating an effect. Most training in this field is done on the job, rather than in formal educational settings.
Being computer savvy is all but essential in today's special effects world. Technicians use CGI, computer-generated images, frequently as an alternative to practical effects. This requires that even practical effects artists have familiarity with computers so they know how to prepare the effect properly for its postproduction treatment. Technicians also plot and render special effects on computers first, well before actually implementing any of the renderings.
Science is a very important part of the special effects world. Physics, chemistry and computer science combine to create the dynamic effects seen on the screen. You can see an example of the scientific knowledge that special effects artists must possess by watching the TV show "Mythbusters." The two hosts, Jamie and Adam, clearly have a wealth of scientific knowledge. They built that knowledge through years working as special effects technicians before starting the show.