If it's "da dat duh dat" on one thing, make it "da dat duh dat" on the other. In other words, don't change your look and feel on your different marketing communications tools. If your website has red, white, and yellow, then use the same colors on your business cards, letterhead, postcards, brochures and and you know whatever else. I've seen so many company's use one type of design for one thing and another for... yes, another:)
Develop a nice logo and use it everywhere. The same one, the same way, and everytime. You need to create brand recognition. changing it around all the time, slows the encoding process down. Sometimes it's ok to change your logo color, but that's usually only when the company is confident about consumer recognition. For example, Target changes the color of their logo in advertisements. But they can do that. Everyone recognized the Target logo, and because it's so common, the likelihood of perceptial blocking occuring is increased. Sometimes changing the color of a well know logo, like Target's get's attention because people expect it to be the red that it normally is.
But anyways, I didn't mean to get into branding issues, but since I have, just read it and learn something from it.
When I say you should keep the same look and feel, I am mostly talking about corporate identy materials, not so much about advertisements. Advertisements can and should be very different and unique. They can still have a similar look and feel, but it is not necessary to keep to it as strictly as with corporate identy related items.
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