How to write the game rules

Here are the rules I wrote for a little sport competition. I am wondering whether it is appropriate in meaning and acceptable in grammar:
"1 minute limit hula hoop"
Player turns the hula hoop quickly and a counter counts the number of rounds that the hula hoop rotates within 1 minute.
Rules:
1. Designated hula hoop should have a radius of 40cm, weight of 1000 grams and white appearance with a 20cm red mark on it.
2. Electric hula hoop and soft hula hoop is not allowed.
3. The initial position of hula hoop with the red mark in front of player's body. When the red mark rotates 360 degrees, we count it as one round.
4. There is no restrict on the direction when turning the hoop.
5. While playing, the hula hoop should turning above player's knee and under the armpit. Hoop's turning outside the scope, stop or drop to the ground within 1 minute are recognized as failure.