I've sewn waves before, but they were on a much larger scale and seemed very easy. Now I'm starting this new quilt and when I tried to sew the first two pieces together, it was a mess. Does anyone have any suggestions on how to do this properly?

I'd pin the beginning and end and the middle, then use a stiletto to move the two edges into alignment as I sew...stopping every few stitches to make sure the next section is in place. It will get easier as you practice, as I'm sure you found out when doing the larger pieces.

Stiletto makes a huge difference for me too.

The directions had me marking each piece and then sticking a straight pin into both marks. They I was supposed to manipulate the material until the pin stood straight up (or out, never was sure). Did this once and it was a huge mess. I will try it again and pin the way you suggested. And I will definitely use my stiletto. Thank you!

What they were describing is one way to make sure that the seamlines match on the two fabrics...I'm a little more casual and just eyeball it, I guess. In those instructions, when the points on the two fabrics are exactly even, the pin that goes thru both points will stand "up" away from the fabric and not at an angle. If the pin is put thru the two points and the points are not aligned exactly, the pin will lie down at an angle...