coloring in two colors - beneath a line ...

[sayhello]

Hello again ,

while trying out the steps i think  i got stuck somehwere

Quote:However, you can use selections, the fuzzy select works with transparent areas.
1) Make a selection on the white line (top) layer
2) Grow the selection by a few pixels to overlap the white line.

well i have added a new layer 
made the selection and third
3. i tried to grow the selection - but believe it or not - i turned it to max  - 70  pixel - but there is now growing visible

see here 

   


well i guess that i did something wrong here 

any ideas -where i missed the path?