Due to issues with the producers, Wang Yang spent over a week following the "Sweetheart" crew, which was far beyond the budgeted time. Only after seeing that Annie Fletcher was fully capable of handling it did he leave the crew and start busying himself with the preparations for "District 9".
Discussing the filming plan with Neill Blomkamp was a major part of the work, but they already had discussions and a consensus well before that. Aside from certain special effects shots that required the use of equipment, "District 9" would be entirely shot using shoulder-mounted and handheld cameras. The camera work would not be kept very stable, naturally, except for some pseudo-documentary news shots and surveillance camera footage.
As for the color and tone of the film, it would be both dark and textured; dark to create a sense of oppression for the audience, and textured for realism.