Question - How to draw waves

[Squiggy]

Well hai,
I'm currently stuck on a picture conatining a lake.
The lake shall have slight waves on it. I've drawn them using a pencil and it looks of - but if I redo them using a felt-tip, I think, they'll look to significant for the picture.
BY the way, the actual picture I'm talking about is the first one in this post.
Help is apprechiated

 

[Angry_Bovine]

Perhaps you could use staggered wave-like lines? Eh... I don't really know how to describe it more than that.

 

[Squiggy]

It's just that they shouldn't take all the eyes' attention when one looks at that picture but rather used as background decoration
that /\___/\___/\___/\___-shaping just looks shitty for a lake