1. Be First - Being the first in the market can be a whole lot better than having a better product than your competitors. Examples include: Heineken which was the first imported beer in the USA and is still the #1 imported beer. The first domestic light beer - Miller Lite. Obviously being first doesn't guarantee success, but it sure does give you an extremely big advantage.
2. Be First In Mind - If you are not going to be first to the market then be the first in the mind of the consumer.
3. Change Category - If there is stiff competition in a particular category it's better to create a new one. Back to the beer example, if there is a dominant import beer player be the first light import beer. It doesn't have to be radically different.
4. Owning Focus - This can be a very important marketing idea. This is where your company or product is associated with a word. Examples include: To "FedEx" something usually means overnight. "Google" means to search. "Xerox" means to copy. McDonald's means fast.
5. Be Honest - As the saying goes, "honesty is the best policy." Do not over promise, do not make false claims, do not do or say one thing and do the other. Consumers can and will find the truth about your products/services faster than I can type this sentence and their reviews will go viral.