For example, if XYZ Corp's EBITDA is $1 billion and its revenue is $10 billion, then its EBITDA to sales ratio is 10%. Generally, a higher value is appreciated for this ratio as that would indicate that the company is able to keep its earnings at a good level via efficient processes that have kept certain expenses low.
However, when comparing company's EBITDA margin, make sure that the companies are in related industries as different size companies in different industries are bound to have different cost structures, which could make comparisons irrelevant.