You use the same principles as if there's only one inequality sign.
But if it makes it easier for you, divide the problem into two separate inequalities:
-1 < 3 - 5m < 3 is the same thing as saying that -1 < 3 - 5m and 3 - 5m < 3.
Now, normal inequality rules apply. First subtract both sides by 3 for both equations:
-4 < -5m and -5m < 0
Then, divide by -5. Remember to reverse the sign direction because you're dividing by a negative:
m < 4/5 and m > 0.
So 0 < m < 4/5. You can verify the answer by throwing a number in between the two values.
And there you have it: inequalities with 2 signs are just two single-sign inequalities put together.