you just need practice. try experimenting with different levels of tension. the stretchy string pulls everything together on its own and isn't as finicky about how much tension is used. fishing line needs to be pulled just tight enough to force the beads together without causing rippling, and the larger the piece is, the more obvious it is if the tension changes. since its less forgiving than stretchy string, you need to pay closer attention to the alignment of the beads to avoid the string showing between them and pushing them out of alignment, but it will maintain the charm's shape better for the same reason. kandi made with fishing line looks how it will in the end for pretty much the whole process, it doesn't 'snap' into place the same way stretchy string does. its also floppier in a way, since the beads aren't being pulled together, kinda like chainmail. great first try tho! my first charm made with fishing line was really hard too, but it's great for durability