A good logo design needs to be able to look good at 20x20 pixels or in a large format such as 15x15 inches. There are many good logos out there, that when shrink in size, they might not look as appealing as in large format or the other way around. Every designer has to make sure that when crating a good logo, it will look just as good in a pixel image or in a big poster. Keep in mind that your logo will be used in countless different ways- letterheads, t-shirts, business cards, invoices, marketing ads.
A good logo has to be easy to remember to any one. By using a simple structure, easy to read fonts and simple graphics, a good memorable logo can be achieved. A memorable logo should be easy to read and comprehend. When we look at some of the most memorable logos, we find that most of them use a rectangular shape, because our eyes find it easier to look at than squares, and they are easier to use on TV ads and on the web. The best way to use your logo is to stick to it, even if you think changing it might be a good option - Don't. Often, companies change their logo, and all it does is confuse your customers and at the end it will lose impact.
3. Must Look Good Without Color
In my personal opinion, I think that a professional designed logo should look good in both, color and in black and white. There is no reason why a logo should not have at least some color, but it must also look good without it. By using a logo that is well design to be printer in color or not, you can use it among all media effectively.
A logo is one of the most important aspects when setting your business credibility. Your logo will be in your business cards, flyers, website, posters, TV commercials, almost in every marketing strategy that you use. So why should you have a complex logo? if we pay attention to some of the most successful companies such as: Microsoft, Google, Coca-Cola, Apple, etc... We will find that none of them use a complex logo, all of them are simple, even some just using text as their logo, nothing else.
In conclusion: Be Creative! A logo should be a big investment for any company. Making your logo as simple as possible will make sure that it is easy to remember to any one. Attempt to use at least only two colors when designing your logo and use a rectangular shape if you can. Please take a look at these logos, it can help you for inspiration.