So here is how you would do it: Projected sales = fixed exp (足ꯠ) divided by 1_ƖǑ% + 27ǔ% + 12ǔ% + 25% (your new profit margin) = 造같 (new sales) You can do this for as many years out as you want. Obviously this is based on your first year's fixed expenses remaining constant and no consideration of depreciation, inflation, or taxes. But most likely you would need to increase your fixed expenses because you're going to probably have more rent, utilities, or such as your business grows. So, you would simple put in your new fixed expense number in place of the existing one for each of the years you would be planning for. So, you see if you decided you wanted a 35% profit margin at year 5 then you could see how much sales it would take to give you that. Now it's also important to know how many more customers you would need as well so you should always look at that unless you have another way of growing your sales other than with new customers.
Do not try to write your business plan in one sitting. As I mentioned in the beginning, for a traditional brick and mortar business, it could take in excess of 100 hours to compile all of the information needed into a comprehensive but yet understandable document. For online businesses, probably not that long. But your final product should be well thought out, well documented and easily understandable.