The best attack is probably the dive.
This depends a bit on the amount of lag/desync but when you get so close to the ball that your arms are about to go up to get the bean
into the ball-pushing position, that is the time to dive for best effect.
Watch out for someone behind the ball as that could trigger an unstoppable counter. This is a very good reason to play Fall Ball with names turned on.
When your teammate is about to hit the dive button for an attack and you are behind the ball with an opponent, grab that opponent to prevent him from getting a jump/dive counter.
Defending
Remember: if no one in your team is goalie, you are it!
The best defense is probably the jump counter. Time your jump so that your opponent launches the ball right
into your jumping bean. You can also use dive in defense and while it could create an even better counter, it is
also a bit trickier.
The Start
If a teammate dives the ball forward towards a teammate running forward from the start, your game of fall ball
might very well see it's first goal in the first seconds.