Hi there! Yes, I'm familiar with WSSI (Weekly Sales & Stock Intake) spreadsheets. They are commonly used in retail businesses to track sales and inventory levels on a weekly basis.

To create your own WSSI spreadsheet, you'll need to start by identifying the key metrics you want to track. These typically include:

1. Sales: This is the total amount of revenue generated by your business during the week.
2. Stock: This is the total amount of inventory you have on hand at the end of the week.
3. Intake: This is the amount of new inventory you received during the week.
4. Markdowns: This is the amount of inventory you marked down during the week.
5. Gross Margin: This is the percentage of sales revenue that you keep after accounting for the cost of goods sold.

Once you've identified these metrics, you can start building your spreadsheet. Here's a step-by-step guide:

1. Open a new Excel spreadsheet and create a table with the following columns: Week, Sales, Stock, Intake, Markdowns, Gross Margin.
2. In the Week column, enter the dates for each week you want to track. You can use the autofill feature to quickly populate this column with dates.
3. In the Sales column, enter the total sales revenue for each week. You can use a formula to calculate this by adding up all of your sales transactions for the week.
4. In the Stock column, enter the total amount of inventory you have on hand at the end of each week. You can use a formula to calculate this by subtracting the total amount of inventory sold during the week from the total amount of inventory you had at the beginning of the week.
5. In the Intake column, enter the amount of new inventory you received during each week. You can use a formula to calculate this by subtracting the total amount of inventory you had at the beginning of the week from the total amount of inventory you had at the end of the week, and then adding back in the amount of inventory sold during the week.
6. In the Markdowns column, enter the amount of inventory you marked down during each week. This will help you track any inventory that you had to discount in order to sell.
7. In the Gross Margin column, enter a formula to calculate the gross margin percentage for each week. This can be calculated by subtracting the cost of goods sold from the total sales revenue, and then dividing that number by the total sales revenue.

That's it! With these columns filled out, you'll have a basic WSSI spreadsheet that you can use to track your sales and inventory levels on a weekly basis. Of course, you can customize this spreadsheet to fit your specific needs and add additional columns or formulas as necessary. Good luck!