Sand...

[Ace of Spades]

Ok, I see what your problem is. When you use the upper left one that everyone is talking about, it leaves a grassy layer on the bottom edge, correct? Well, to fix this, you use the upper left one, like everyone is saying to get the grass to sand effect. THEN, on the area that it has the extra grasssy edge, use the one that has JUST sand, however, while placing the sand on that edge, hold down shift while doing it. Now, when you're done placing the sand to rid yourself of the extra grassy layer, let go of your mouse first, not shift. Got it? Hopefully this will solve your problem.

[Zeigue]

Thank You AOS! it worked! thanks to everybody else who helped me too!.