In their book Blue Ocean Strategy W. Chan and Renee Mauborgne constructed a strategy canvas as the key diagnostic tool for building a unique business strategy. In the first place a Blue Ocean Strategy is about finding space in a market (a blue-ocean) where your product or business is sufficiently differentiated such that you are not competing head to head with your competitors.
A strategy canvas is a graph that on the horizontal axis lists the competitive factors of any particular industry while on the y axis your (or your competitors) offerings for those competitive factors are graded. Here is a hypothetical example for web development in Queenstown:
One business clearly competes on price and offers a substantially different content management system. At the other end of the scale one business (the dark blue) differentiates itself on the quality of the developer and is not competitive on price.
The advantage of the strategy canvas is that it allows you to identify the blue-oceans spaces in a market and focus your business strategy on those areas as opposed to competing in the crowded space. For example in the above scenario by not competing on price the dark blue company has to be able compete on an alternative offering.
I always use a strategy canvas when consulting with clients on their web strategy and business strategies. Here is a great excel template for deriving your own strategy canvas. It shows both the comparative canvas but also a value curve which you can monitor over time as a KPI to see that your business execution is going in the same direction as your strategy.