With so many roller-bladers used to brakes being in the back of a skate, switching to an old fashioned quad skate can be jarring! But the front brake is a good design and can be usually used to stop no matter if you are skating outside or have somehow found yourself at an old fashioned roller disco!
Begin skating with your quad skates, normally.
When you decide to stop, slowly tip the front part of your dominant foot (usually the same as your dominant hand) down towards the ground.
As you feel the front brake begin to scrape the ground, push your foot harder and turn your other foot slightly on an angle, away from your body. (Your knee and your foot should always be facing the same direction).
This will cause you to stop.
Practice starting and stopping at different speeds until you are used to using a front brake.
When you are very comfortable with front braking with your dominant foot, begin to practice with your other foot.
Braking with a front brake takes more movement then braking with a back brake.