Make sure the number of columns in the first matrix equals the number of rows in the second matrix
Create a result matrix with the number of rows from the first matrix and the number of columns from the second matrix
For each position in the result matrix, take the row from the first matrix and the column from the second matrix
Multiply matching entries from that row and column
Add all the products together
Put the sum into the corresponding position in the result matrix
Repeat for every position in the result matrix