For beginners, it can be a hard time having your guard passed and recover the guard after being passed. Consider playing a safer guard like closed guard, where you control the opponent with your legs around his body. From closed guard, there are various submission attacks and sweeps without danger of being passed right away. Also most sweeps if done correctly will end up in mount, considering a competition that would be 2 points for the sweep plus 4 points for mount right away.
The video shows a basic closed guard attack called flower sweep, that is just like described above, the sweep ends up in mount. It requires the basic movements for Brazilian Jiu Jitsu, like moving the hip, getting the right grips on the kimono, and using with the proper muscles.
The move itself is pretty simple but has some mandatory details. You start off from closed guard and get your grip on the same side sleeve. The video shows a 4 finger grip, pay attention to the details so you don’t get the grip break right away. You keep the grip strong and try to hold the sleeve in the centerline of your body while you shift your hips slightly in the same direction. Put your same side foot on the ground as you would bridge with your body bend to the opposite. Grab the same side pants with your other hand and push with your leg into the body of your partner to get the sweep.