Please help me write a factorial in MIPS Assembly.

The pseudocode looks like:

factorial(i) {

int num = 1;

for (int i = 1; i <= n; i++) {

num *= 1

}

return num

}

This is a method that I will use inside another method. n is stored in register $s0, i is stored in register $s1. Register $s2 is already storing another variable in another method. How would I make this method in MIPS? Please explain the steps.