Open Gym: Use the gym space and equipment for your own training needs.
Sparring: Come and spar! Use the gym's gloves and headgear if you need them, but bring your own mouth-guard! And make sure to follow the sparring rules posted by the door.
Get equipped: mouth guard, head guard, hand wraps, 16oz. gloves, shin-guards if applicable
Communicate your boundaries
Start out light
They're your partner, not your enemy
Be mindful of others in the gym
Let your partner recover
Talk with your partner afterwards
Be gracious in giving and receiving advice
Have fun - Roll with the punches