The order that works
Good tests follow three steps. First, decide the smallest improvement worth finding and calculate the sample size. Second, run the test until you reach that sample, without stopping early because the numbers look good. Third, check the result with a significance test and look at the size of the difference as well as the p-value.
After the test
A significant result tells you the difference is probably real. To find out whether it is worth acting on, estimate the extra orders and profit with the CRO uplift calculator.