Well i made i pretty much the same way as i did with my water signature, exept the gridlines.
http://img158.echo.cx/img158/796/chr...nature18cj.gif
Lighter version:
http://img183.echo.cx/img183/193/chr...nature29wp.gif
Even More Lighter:
http://img183.echo.cx/img183/5548/ch...nature35tx.gif