Many small businesses that are strapped for cash and working out how to manage cash flow because of Covid-19, are applying for relief from the federal government through the SBA.

To understand how much you'll need, it's important to understand "precisely" how the events of the past few weeks have impacted your business, according to Brooke Evans, CEO of CFO Alliance, a financial outsourcing firm. Here are her tips for getting a handle on your cash.

Start with weekly cash transactions. 

In optimal situations, Evans recommends a 13-week cash forecast--and in times like this it can be even more helpful. She recommends finding the data-savvy person in your office, which might be you, and start doing a little "Excel jockeying." You'll want to structure your actual cash transactions--any money coming in or going out--into a weekly format for the most accurate picture of what is happening in a rapidly changing situation.

Next, decide how you want to sort those transactions, such as payroll or bills, based on which expense categories are most meaningful to your business model. For example, a restaurant might have a category for food inventory, while a tech company might include cloud computing costs, Evans said. Whatever you choose, create a key to sort them automatically, code historical data, and then start working with real-time figures.

You can also input your receivables, or expected payments, and when you should be receiving them. Evans said this will allow you to communicate with your stakeholders, investors, and vendors, about when you'll be able to pay them as well. Communication is critical.

Be conservative with sales forecasts.

"I would be extremely conservative on my sales forecast because that's going to tell you where you need to make changes," Evans said. Changes could include shifting your strategy or temporarily furloughing employees, she said. 

Sales pipelines are more likely to be dramatically impacted by Covid-19, so err on the side of caution and use your best judgment to sort out which sectors of your business are taking the hardest hits.

Build your cash forecast.

Evans recommends a middle-of-the-road approach with your cash while creating a more comprehensive "risks" section. 

Once you get this built, according to Evans, what seemed like a scattered puzzle will now start to make sense. "Now, you can see where all the pieces are, and you need to figure out how to make your edges, and how to fill in the middle," she said. 

Free tool to model your cash flow 

This free 13-week cash flow tool can help you put these elements into one spreadsheet. The template is available from CFO Alliance with a consultation at no charge. It's not necessarily "easy to use," Evans said. "But it is practical and highly effective once it's built." Evans is also hosting a free webinar for business owners at 2 p.m. Eastern time on March 31 to learn more about it.