Here is an example of a Summary Sheet I use when preparing a forecasted cash flow. It provides areas for detailing each Source and Use of cash. A simple report like this is easy to read and provides space to document assumptions.
The last section of the forecasted cash flow provides a running balance of the projected cash balance based on these set of assumptions. While that this will never be 100% accurate (what in life is?) you can easily see the projected cash balance and determine if there is a projected shortfall in the future. Having that information at your fingertips allows you to take action to mitigate any potential shortfalls.
(Click on the image to view larger)