Each column represents one square. Round 1 is the center round and round 7 is the outer round. I put the round number in the row of the color that I used for that round. So each column should have the numbers 1-7 in 7 of the cells. Finally I used the "countif" function in Excel to count the number of times a color appeared in each round, and added a total of these for the number of squares on the right-hand side of the row. I can add columns as needed. For two of the squares, I had repeated a color. So I only put the first occurrence of that color in the square's column, and I added one to the appropriate "countif" cell on the right for the second occurence.
According to the spreadsheet, these colors appear in the rounds I've chosen for them 1, 0, 2, 0, 1, 0 and 0 times in rounds 1 to 7. So if I stick with this arrangement I will have three squares with gold in round 3. I prefer this to the alternative with yellow in round 3 and gold in round 1, even though I've never used the gold yarn in round 1. So I'll stay with the arrangement I chose.
Here's the finished square. In the final version, I switched the aqua and eggplant bobbles.