How do you create a digital marketing strategy without a proper brief from the client?

A successful Marketing strategy is always dependent on the client's need and expectation. And as a matter of fact, success or failure of anything is dependent on fulfilment of expectation, what you find to be successful may not be to another. So, how do you strategize when you don't know what is expected out of the campaign and as @Farooq has rightly put it, its like driving without any destination.

Without client brief Digital Marketing strategy cannot be initiated. Its like driving someones car to unknown location where you might lost anytime. Initial brief is definitely required to show client the line of action.

what do you mean by a proper brief? has he not provided any information such as his product/service, market and couple of competitor names? If he has then we can go ahead creating a digital proposal for him...