I just used fishing line on the Deadpool I submitted today. I actually did it by putting the glue on the figure, not the fishing line. Its just that the thing you have to remember is that less is more in this instance. It definitely sticks better when you use just a little glue instead of a big glob of it. Like Green said, just do a little bit at a time, and it can have great, great results
It's pretty simple. Apply the glue to the fish line, not the figure. Work in small sections, if you try to glue the whole thing at once it'll be much harder. That's about it.